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356 results on '"University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)"'

1. The Magnetic Genome of Two-Dimensional van der Waals Materials

Author: Qing Hua Wang, Amilcar Bedoya-Pinto, Mark Blei, Avalon H. Dismukes, Assaf Hamo, Sarah Jenkins, Maciej Koperski, Yu Liu, Qi-Chao Sun, Evan J. Telford, Hyun Ho Kim, Mathias Augustin, Uri Vool, Jia-Xin Yin, Lu Hua Li, Alexey Falin, Cory R. Dean, Fèlix Casanova, Richard F. L. Evans, Mairbek Chshiev, Artem Mishchenko, Cedomir Petrovic, Rui He, Liuyan Zhao, Adam W. Tsen, Brian D. Gerardot, Mauro Brotons-Gisbert, Zurab Guguchia, Xavier Roy, Sefaattin Tongay, Ziwei Wang, M. Zahid Hasan, Joerg Wrachtrup, Amir Yacoby, Albert Fert, Stuart Parkin, Kostya S. Novoselov, Pengcheng Dai, Luis Balicas, Elton J. G. Santos, Arizona State University [Tempe] (ASU), Max Planck Institute of Microstructure Physics, Instituto de Ciencia Molecular (ICMol), Universitat de València (UV), Columbia University [New York], Department of Physics [Harvard University], Harvard University, Universität Duisburg-Essen = University of Duisburg-Essen [Essen], National University of Singapore (NUS), Condensed Matter Physics and Materials Sciences Department, Brookhaven National Laboratory [Upton, NY] (BNL), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), Los Alamos National Laboratory (LANL), 1. Physikalisches Institut [Stuttgart], Universität Stuttgart [Stuttgart], Kumoh National Institute of Technology [Gumi], Kumoh National Institute of Technology [Gyeongsangbuk-do], Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), SUPA School of Physics and Astronomy [Edinburgh], University of Edinburgh, Department of Physics, Princeton University (DPPU), Princeton University, Institute for Frontier Materials (IFM), Deakin University [Burwood], Department of Physics, Columbia University, Ikerbasque - Basque Foundation for Science, Basque Research and Technology Alliance (BRTA), University of York [York, UK], SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), University of Manchester [Manchester], Texas Tech University [Lubbock] (TTU), Department of Physics, University of Michigan, University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Institute for Quantum Computing [Waterloo] (IQC), University of Waterloo [Waterloo], Heriot-Watt University [Edinburgh] (HWU), Laboratory for Muon-Spin Spectroscopy (LMU), Paul Scherrer Institute (PSI), National High Magnetic Field Laboratory (NHMFL), Florida State University [Tallahassee] (FSU), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Princeton Institute for the Science and Technology of Materials, Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), THALES [France]-Centre National de la Recherche Scientifique (CNRS), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Rice University [Houston], Donostia International Physics Center - DIPC (SPAIN), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), and ANR-18-CE24-0007,MAGICVALLEY,Polarisation de vallée induite par couplage d'échange magnétique dans les matériaux 2D à grande échelle(2018)
Subjects: 2D magnetic materials, Magnetic Phenomena, neutron scattering, General Engineering, General Physics and Astronomy, Spintronics, Device engineering, Computing Methodologies, Magnetic imaging, atomistic spin dynamics, Topological properties, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], van der Waals, Heterostructures, Quantum Theory, General Materials Science, magneto-optical effect, Spin excitations, theory
Abstract: International audience; Magnetism in two-dimensional (2D) van der Waals (vdW) materials has recently emerged as one of the most promising areas in condensed matter research, with many exciting emerging properties and significant potential for applications ranging from topological magnonics to low-power spintronics, quantum computing, and optical communications. In the brief time after their discovery, 2D magnets have blossomed into a rich area for investigation, where fundamental concepts in magnetism are challenged by the behavior of spins that can develop at the single layer limit. However, much effort is still needed in multiple fronts before 2D magnets can be routinely used for practical implementations. In this comprehensive review, prominent authors with expertise in complementary fields of 2D magnetism (i.e., synthesis, device engineering, magneto-optics, imaging, transport, mechanics, spin excitations, and theory and simulations) have joined together to provide a genome of current knowledge and a guideline for future developments in 2D magnetic materials research.
Published: 2022
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2. Phase diagram of twisted bilayer graphene at filling factor ν = ± 3

Author: Fang Xie, Jian Kang, B. Andrei Bernevig, Oskar Vafek, Nicolas Regnault, Department of Physics, Princeton University (DPPU), Princeton University, Rice University [Houston], ShanghaiTech University [Shanghai], Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, National High Magnetic Field Laboratory (NHMFL), Florida State University [Tallahassee] (FSU), Théorie de la Matière Condensée, Laboratoire de physique de l'ENS - ENS Paris (LPENS), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), European Project: 101017733 ,QuantERA II, European Project: 731473,QuantERA, and European Project: 101020833,SuperFlat
Subjects: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Mesoscale and Nanoscale Physics, [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el]
Abstract: We study the correlated insulating phases of twisted bilayer graphene (TBG) in the absence of lattice strain at integer filling $\nu=\pm3$. Using the self-consistent Hartree-Fock method on a particle-hole symmetric model and allowing translation symmetry breaking terms, we obtain the phase diagram with respect to the ratio of $AA$ interlayer hopping $(w_0)$ and $AB$ interlayer hopping $(w_1)$. When the interlayer hopping ratio is close to the chiral limit ($w_0/w_1 \lesssim 0.5$), a quantum anomalous Hall state with Chern number $\nu_c = \pm 1$ can be observed consistent with previous studies. Around the realistic value $w_0/w_1 \approx 0.8$, we find a spin and valley polarized, translation symmetry breaking, state with $C_{2z}T$ symmetry, a charge gap and a doubling of the moir\'e unit cell, dubbed the $C_{2z}T$ stripe phase. The real space total charge distribution of this $C_{2z}T$ stripe phase in the flat band limit does not have modulation between different moir\'e unit cells, although the charge density in each layer is modulated, and the translation symmetry is strongly broken. Other symmetries, including $C_{2z}$, $C_{2x}$ and particle-hole symmetry $P$, and the topology of the $C_{2z}T$ stripe phase are also discussed in detail. We observed braiding and annihilation of the Dirac nodes by continuously turning on the order parameter to its fully self-consistent value, and provide a detailed explanation of the mechanism for the charge gap opening despite preserving $C_{2z}T$ and valley $U(1)$ symmetries. In the transition region between the quantum anomalous Hall phase and the $C_{2z}T$ stripe phase, we find an additional competing state with comparable energy corresponding to a phase with a tripling of the moir\'e unit cell., Comment: 39 pages, 33 figures
Published: 2023
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3. SuperpixelGridMasks Data Augmentation:Application to Precision Health and Other Real-world Data

Author: Karim Hammoudi, Adnane Cabani, Bouthaina Slika, Halim Benhabiles, Fadi Dornaika, Mahmoud Melkemi, Institut de Recherche en Informatique Mathématiques Automatique Signal - IRIMAS - UR 7499 [IRIMAS], École Supérieure d’Ingénieurs en Génie Électrique [ESIGELEC], Euskal Herriko Unibertsitatea [Guipúzcoa] [EHU], University of the Basque Country/Euskal Herriko Unibertsitatea [UPV/EHU], Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN], Bio-Micro-Electro-Mechanical Systems - IEMN [BIOMEMS - IEMN], JUNIA [JUNIA], Institut de Recherche en Informatique Mathématiques Automatique Signal - IRIMAS - UR 7499 (IRIMAS), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)), École Supérieure d’Ingénieurs en Génie Électrique (ESIGELEC), Euskal Herriko Unibertsitatea [Guipúzcoa] (EHU), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), Bio-Micro-Electro-Mechanical Systems - IEMN (BIOMEMS - IEMN), Université catholique de Lille (UCL)-Université catholique de Lille (UCL)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), JUNIA (JUNIA), and Université catholique de Lille (UCL)
Subjects: [SPI]Engineering Sciences [physics], Artificial Intelligence, Health Informatics, Computer Science Applications, Information Systems
Abstract: ressources projet: https://github.com/hammoudiproject/SuperpixelGridMasksdatasets used for the article: 1 Dataset Chest X-Ray Images: https://www.kaggle.com/datasets/paultimothymooney/chest-xray-pneumonia2 A PASCAL VOC dataset: http://host.robots.ox.ac.uk/pascal/VOC/databases.html#VOC2005_1; International audience; A novel approach of data augmentation based on irregular superpixel decomposition is proposed. This approach called SuperpixelGridMasks permits to extend original image datasets that are required by training stages of machine learning-related analysis architectures towards increasing their performances. Three variants named SuperpixelGridCut, SuperpixelGridMean, and SuperpixelGridMix are presented. These grid-based methods produce a new style of image transformations using the dropping and fusing of information. Extensive experiments using various image classification models as well as precision health and surrounding real-world datasets show that baseline performances can be significantly outperformed using our methods. The comparative study also shows that our methods can overpass the performances of other data augmentations. SuperpixelGridCut, SuperpixelGridMean, and SuperpixelGridMix codes are publicly available at https://github.com/hammoudiproject/SuperpixelGridMasks.
Published: 2023
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4. Automatically weighted binary multi-view clustering via deep initialization (AW-BMVC)

Author: Khamis Houfar, Djamel Samai, Fadi Dornaika, Azeddine Benlamoudi, Khaled Bensid, Abdelmalik Taleb-Ahmed, Université Kasdi Merbah Ouargla, Universitat Autònoma de Barcelona (UAB), Ikerbasque - Basque Foundation for Science, University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Center for Machine Vision Research (CMV), University of Oulu, Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), COMmunications NUMériques - IEMN (COMNUM - IEMN), INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Université catholique de Lille (UCL)-Université catholique de Lille (UCL)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université Polytechnique Hauts-de-France (UPHF), The authors gratefully acknowledge the Directorate General for Scientific Research and Technological Development (DGRSDT) of Algeria for the financial support to this work. This work is part of the grant PID2021-126701OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe., Universitat Autònoma de Barcelona [UAB], University of the Basque Country/Euskal Herriko Unibertsitatea [UPV/EHU], Center for Machine Vision Research [CMV], Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN], COMmunications NUMériques - IEMN [COMNUM - IEMN], and Université Polytechnique Hauts-de-France [UPHF]
Subjects: [SPI]Engineering Sciences [physics], Discrete representation, Artificial Intelligence, Multi-view clustering, Anchors, Signal Processing, BD-FFT, Large scale, Computer Vision and Pattern Recognition, Software
Abstract: International audience; Clustering is inherently a process of exploratory data analysis. It has attracted more attention recently because much real-world data consists of multiple representations or views. However, it becomes increasingly problematic when dealing with large and heterogeneous data. It is worth noting that several approaches have been developed to increase computational efficiency, although most of them have some drawbacks: (1) Most existing techniques consider equal or static weights to quantify importance across different views and samples, so common and complementary features cannot be used. (2) The clustering task is performed by arbitrary initialization without caring about the rich structure of the joint discrete representation, and thus poorly executed. In this paper, we propose a novel approach called “Auto-Weighted Binary Multi-View Clustering Via Deep Initialization” for large-scale multi-view clustering based on two main scenarios. First, we consider the distinction between different views based on the importance of samples, and therefore apply a dynamic learning strategy for the automatic weighting of views and samples. Second, in the context of initializing binary clustering, we develop a new CNN feature and use a low-dimensional binary embedding by exploiting the efficient capabilities of Fourier mapping. Moreover, our approach simultaneously learns a joint discrete representation and performs direct clustering using a constrained binary matrix factorization; the optimization problem is perfectly solved in a unified learning model. Experimental results conducted on several challenging datasets demonstrate the effectiveness and superiority of the proposed approach over state-of-the-art methods in terms of accuracy, normalized mutual information, and purity.
Published: 2023
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5. General construction and topological classification of crystalline flat bands

Author: Dumitru Călugăru, Aaron Chew, Luis Elcoro, Yuanfeng Xu, Nicolas Regnault, Zhi-Da Song, B. Andrei Bernevig, Department of Physics, Princeton University (DPPU), Princeton University, University of the Basque Country [Bizkaia] (UPV/EHU), Max Planck Institute of Microstructure Physics, Théorie de la Matière Condensée, Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Laboratoire de physique de l'ENS - ENS Paris (LPENS), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)
Subjects: Electronic properties and materials, 0103 physical sciences, General Physics and Astronomy, Topological insulators, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 01 natural sciences, ComputingMilieux_MISCELLANEOUS, 010305 fluids & plasmas
Abstract: A general theoretical technique is introduced to identify materials that host flat bands. Applying topological quantum chemistry provides the generating bases for these flat bands in all space groups. Exotic phases of matter can emerge from the interplay between strong electron interactions and non-trivial topology. Materials that have non-dispersing bands in their electronic band structure, such as twisted bilayer graphene, are prime candidates for strongly interacting physics. However, existing theoretical models for obtaining these 'flat bands' in crystals are often too restrictive for experimental realizations. Here we present a generic theoretical technique for constructing perfectly flat bands from bipartite crystalline lattices. Our prescription encapsulates and generalizes the various flat-band models in the literature and is applicable to systems with any orbital content, with or without spin-orbit coupling. Using topological quantum chemistry, we build a complete topological classification in terms of symmetry eigenvalues of all the gapped and gapless flat bands. We also derive criteria for the existence of symmetry-protected band touching points between the flat and dispersive bands, and identify the gapped flat bands as prime candidates for fragile topological phases. Finally, we show that the set of all perfectly flat bands is finitely generated and construct the corresponding bases for all 1,651 Shubnikov space groups.
Published: 2022
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6. Comparison of clinical rating scales in genetic frontotemporal dementia within the GENFI cohort

Author: Peakman, Georgia, Russell, Lucy L., Convery, Rhian S., Nicholas, Jennifer M., van Swieten, John C., Jiskoot, Lize C., Moreno, Fermin, Sanchez-Valle, Raquel, Laforce, Robert, Graff, Caroline, Masellis, Mario, Tartaglia, Maria Carmela, Rowe, James B., Borroni, Barbara, Finger, Elizabeth, Synofzik, Matthis, Galimberti, Daniela, Vandenberghe, Rik, de Mendonça, Alexandre, Butler, Chris R., Gerhard, Alex, Ducharme, Simon, Le Ber, Isabelle, Tagliavini, Fabrizio, Santana, Isabel, Pasquier, Florence, Levin, Johannes, Danek, Adrian, Otto, Markus, Sorbi, Sandro, Rohrer, Jonathan D., Afonso, Sónia, Almeida, Maria Rosario, Anderl-Straub, Sarah, Andersson, Christin, Antonell, Anna, Archetti, Silvana, Arighi, Andrea, Balasa, Mircea, Barandiaran, Myriam, Bargalló, Nuria, Bartha, Robart, Bender, Benjamin, Benussi, Alberto, Bertoux, Maxime, Bertrand, Anne, Bessi, Valentina, Black, Sandra, Bocchetta, Martina, Borrego-Ecija, Sergi, Bras, Jose, Brice, Alexis, Bruffaerts, Rose, Camuzat, Agnès, Cañada, Marta, Cantoni, Valentina, Caroppo, Paola, Cash, David, Castelo-Branco, Miguel, Colliot, Olivier, Cope, Thomas, Deramecourt, Vincent, de Arriba, María, Di Fede, Giuseppe, Díez, Alina, Duro, Diana, Fenoglio, Chiara, Ferrari, Camilla, Ferreira, Catarina B., Fox, Nick, Freedman, Morris, Fumagalli, Giorgio, Funkiewiez, Aurélie, Gabilondo, Alazne, Gasparotti, Roberto, Gauthier, Serge, Gazzina, Stefano, Giaccone, Giorgio, Gorostidi, Ana, Greaves, Caroline, Guerreiro, Rita, Heller, Carolin, Hoegen, Tobias, Indakoetxea, Begoña, Jelic, Vesna, Karnath, Hans-Otto, Keren, Ron, Kuchcinski, Gregory, Langheinrich, Tobias, Lebouvier, Thibaud, Leitão, Maria João, Lladó, Albert, Lombardi, Gemma, Loosli, Sandra, Maruta, Carolina, Mead, Simon, Meeter, Lieke, Miltenberger, Gabriel, van Minkelen, Rick, Mitchell, Sara, Moore, Katrina, Nacmias, Benedetta, Nelson, Annabel, Öijerstedt, Linn, Olives, Jaume, Ourselin, Sebastien, Padovani, Alessandro, Panman, Jessica, Papma, Janne M., Pijnenburg, Yolande, Polito, Cristina, Premi, Enrico, Prioni, Sara, Prix, Catharina, Rademakers, Rosa, Redaelli, Veronica, Rinaldi, Daisy, Rittman, Tim, Rogaeva, Ekaterina, Rollin, Adeline, Rosa-Neto, Pedro, Rossi, Giacomina, Rossor, Martin, Santiago, Beatriz, Saracino, Dario, Sayah, Sabrina, Scarpini, Elio, Schönecker, Sonja, Seelaar, Harro, Semler, Elisa, Shafei, Rachelle, Shoesmith, Christen, Swift, Imogen, Tábuas-Pereira, Miguel, Tainta, Mikel, Taipa, Ricardo, Tang-Wai, David, Thomas, David L., Thompson, Paul, Thonberg, Hakan, Timberlake, Carolyn, Tiraboschi, Pietro, Todd, Emily, van Damme, Philip, Vandenbulcke, Mathieu, Veldsman, Michele, Verdelho, Ana, Villanua, Jorge, Warren, Jason, Wilke, Carlo, Woollacott, Ione, Wlasich, Elisabeth, Zetterberg, Henrik, Zulaica, Miren, Neurology, Amsterdam Neuroscience - Neurodegeneration, University College of London [London] (UCL), London School of Hygiene and Tropical Medicine (LSHTM), Erasmus University Medical Center [Rotterdam] (Erasmus MC), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona (UB), Centre Hospitalier Université Laval [Quebec] (CHUL), CHU de Québec–Université Laval, Université Laval [Québec] (ULaval)-Université Laval [Québec] (ULaval), Karolinska Institutet [Stockholm], University of Toronto, University of Cambridge [UK] (CAM), University of Brescia, University of Western Ontario (UWO), Universitätsklinikum Tübingen - University Hospital of Tübingen, Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Lusófona University [Lisbon], University of Oxford, University of Manchester [Manchester], McGill University = Université McGill [Montréal, Canada], Institut du Cerveau = Paris Brain Institute (ICM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de la Mémoire et de la Maladie d'Alzheimer [CHU Pitié-Salpétriêre] (IM2A), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Service de Neurologie [CHU Pitié-Salpêtrière], IFR70-CHU Pitié-Salpêtrière [AP-HP], Fondazione IRCCS Istituto Neurologico 'Carlo Besta', University of Coimbra [Portugal] (UC), Lille Neurosciences & Cognition - U 1172 (LilNCog), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Ludwig-Maximilians-Universität München (LMU), University of Ulm (UUlm), Università degli Studi di Firenze = University of Florence (UniFI), HAL-SU, Gestionnaire, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), University of Oxford [Oxford], Institut du Cerveau et de la Moëlle Epinière = Brain and Spine Institute (ICM), Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de la Mémoire et de la Maladie d'Alzheimer [Paris] (IM2A), Sorbonne Université (SU), Lille Neurosciences & Cognition - U 1172 (LilNCog (ex-JPARC)), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Peakman, Georgia [0000-0002-3319-138X], Convery, Rhian S [0000-0002-9477-1812], Van Swieten, John C [0000-0001-6278-6844], Jiskoot, Lize C [0000-0002-1120-1858], Rowe, James B [0000-0001-7216-8679], Borroni, Barbara [0000-0001-9340-9814], Finger, Elizabeth [0000-0003-4461-7427], Galimberti, Daniela [0000-0002-9284-5953], Gerhard, Alex [0000-0002-8071-6062], Ducharme, Simon [0000-0002-7309-1113], Le Ber, Isabelle [0000-0002-2508-5181], Danek, Adrian [0000-0001-8857-5383], Otto, Markus [0000-0002-6647-5944], Sorbi, Sandro [0000-0002-0380-6670], Rohrer, Jonathan D [0000-0002-6155-8417], Apollo - University of Cambridge Repository, and Genetic FTD Initiative (GENFI)
Subjects: Oncology, Medizin, LANGUAGE, Disease, Genetic FTD Initiative (GENFI), Cohort Studies, 0302 clinical medicine, diagnosis [Frontotemporal Dementia], ddc:150, C9orf72, CRITERIA, 030212 general & internal medicine, frontotemporal dementia, C9orf72 Protein, Cross-Sectional Studies, Disease Progression, Frontotemporal Dementia, Humans, Mutation, tau Proteins, Mental Status and Dementia Tests, VERSION, 11 Medical and Health Sciences, Psychiatry, UTILITY, DDC 150 / Psychology, biology, FTD, 17 Psychology and Cognitive Sciences, Psychiatry and Mental health, Mutation (genetic algorithm), Cohort, [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], medicine.symptom, FTLD, Life Sciences & Biomedicine, Alzheimer’s disease, Frontotemporal dementia, medicine.medical_specialty, Clinical Dementia Rating, Tau protein, Clinical Neurology, Alzheimerkrankheit, [SDV.GEN.GH] Life Sciences [q-bio]/Genetics/Human genetics, DIAGNOSIS, Asymptomatic, VALIDATION, 03 medical and health sciences, SDG 3 - Good Health and Well-being, Internal medicine, mental disorders, medicine, ddc:610, [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC], Neurodegeneration, Science & Technology, Neurology & Neurosurgery, [SDV.GEN.GPO]Life Sciences [q-bio]/Genetics/Populations and Evolution [q-bio.PE], business.industry, MUTATIONS, medicine.disease, [SDV.GEN.GH]Life Sciences [q-bio]/Genetics/Human genetics, biology.protein, [SDV.GEN.GPO] Life Sciences [q-bio]/Genetics/Populations and Evolution [q-bio.PE], Surgery, Neurology (clinical), Neurosciences & Neurology, business, 030217 neurology & neurosurgery
Abstract: BackgroundTherapeutic trials are now underway in genetic forms of frontotemporal dementia (FTD) but clinical outcome measures are limited. The two most commonly used measures, the Clinical Dementia Rating (CDR)+National Alzheimer’s Disease Coordinating Center (NACC) Frontotemporal Lobar Degeneration (FTLD) and the FTD Rating Scale (FRS), have yet to be compared in detail in the genetic forms of FTD.MethodsThe CDR+NACC FTLD and FRS were assessed cross-sectionally in 725 consecutively recruited participants from the Genetic FTD Initiative: 457 mutation carriers (77 microtubule-associated protein tau (MAPT), 187 GRN, 193 C9orf72) and 268 family members without mutations (non-carrier control group). 231 mutation carriers (51 MAPT, 92 GRN, 88 C9orf72) and 145 non-carriers had available longitudinal data at a follow-up time point.ResultsCross-sectionally, the mean FRS score was lower in all genetic groups compared with controls: GRN mutation carriers mean 83.4 (SD 27.0), MAPT mutation carriers 78.2 (28.8), C9orf72 mutation carriers 71.0 (34.0), controls 96.2 (7.7), p, publishedVersion
Published: 2022
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7. Molecular recognition of a membrane-anchored HIV-1 pan-neutralizing epitope

Author: Johana Torralba, Igor de la Arada, Angélica Partida-Hanon, Edurne Rujas, Madalen Arribas, Sara Insausti, Claire Valotteau, Javier Valle, David Andreu, José M. M. Caaveiro, María Angeles Jiménez, Beatriz Apellániz, Lorena Redondo-Morata, José L. Nieva, European Commission, University of the Basque Country/Euskal Herriko Unibertsitatea [UPV/EHU], Adhésion et Inflammation [LAI], Kyushu University, Centre d’Infection et d’Immunité de Lille - INSERM U 1019 - UMR 9017 - UMR 8204 [CIIL], Institut National de la Santé et de la Recherche Médicale [INSERM], Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] [UPV/EHU], University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Rocasolano Physical Chemistry Institute, Adhésion et Inflammation (LAI), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Universitat Pompeu Fabra [Barcelona] (UPF), Centre d’Infection et d’Immunité de Lille - INSERM U 1019 - UMR 9017 - UMR 8204 (CIIL), Institut Pasteur de Lille, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Ministerio de Ciencia e Innovación (España), Eusko Jaurlaritza, Japan Society for the Promotion of Science, Agence Nationale de la Recherche (France), Universidad Pompeu Fabra, Consejo Superior de Investigaciones Científicas (España), Arada, Igor de la, Arribas, Madalen, Caaveiro, José M. M., Jiménez, M. Angeles, Apellániz, Beatriz, Redondo-Morata, Lorena, and Nieva, José L.
Subjects: Membrane biophysics, Epitopes, Nanoscale biophysics, [SDV]Life Sciences [q-bio], Immunology, Lipid Bilayers, HIV-1, Medicine (miscellaneous), HIV Antibodies, General Agricultural and Biological Sciences, General Biochemistry, Genetics and Molecular Biology, HIV Envelope Protein gp41
Abstract: 14 pags., 6 figs., 1 tab., Antibodies against the carboxy-terminal section of the membrane-proximal external region (C-MPER) of the HIV-1 envelope glycoprotein (Env) are considered as nearly pan-neutralizing. Development of vaccines capable of producing analogous broadly neutralizing antibodies requires deep understanding of the mechanism that underlies C-MPER recognition in membranes. Here, we use the archetypic 10E8 antibody and a variety of biophysical techniques including single-molecule approaches to study the molecular recognition of C-MPER in membrane mimetics. In contrast to the assumption that an interfacial MPER helix embodies the entire C-MPER epitope recognized by 10E8, our data indicate that transmembrane domain (TMD) residues contribute to binding affinity and specificity. Moreover, anchoring to membrane the helical C-MPER epitope through the TMD augments antibody binding affinity and relieves the effects exerted by the interfacial MPER helix on the mechanical stability of the lipid bilayer. These observations support that addition of TMD residues may result in more efficient and stable anti-MPER vaccines., This study was supported by MCIN/AEI/10.13039/501100011033 - “ERDF A way of making Europe” (Grant PID2021-126014OB-I00 to J.L.N. and B.A.), MCIN/AEI/ 10.13039/501100011033 (Grant PID2020-112821GB-I00 to M.A.J.), Basque Government (Grant: IT1449-22 to J.L.N. and B.A.) and Kiban-B grant 20H03228 from JSPS to J.M.M.C. L.R.-M. acknowledges funding from the Agence National de la Recherche (ANR), as part of the ‘Investments d′Avenir’ Program (I-SITE ULNE/ANR-16-IDEX0004 ULNE). This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 895819 (to C.V.). Work at Pompeu Fabra University was supported by the María de Maeztu network of Units of Excellence of the Spanish Ministry of Science and Innovation. Technical assistance from Miguel García-Porras is greatly acknowledged. The NMR experiments were performed in the “Manuel Rico” NMR laboratory, LMR, CSIC, a node of the Spanish Large-Scale National Facility ICTS R-LRB
Published: 2022
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8. Topological materials discovery from crystal symmetry

Author: Maia G. Vergniory, Luis Elcoro, Benjamin J. Wieder, Titus Neupert, Alexey A. Soluyanov, Claudia Felser, Zhijun Wang, Nicolas Regnault, B. Andrei Bernevig, Barry Bradlyn, Jennifer Cano, Department of Physics [MIT Cambridge], Massachusetts Institute of Technology (MIT), Department of Physics, Northeastern University, Northeastern University [Boston], Department of Physics, Princeton University (DPPU), Princeton University, Department of Electrical and Computer Engineering [Urbana] (University of Illinois), University of Illinois at Urbana-Champaign [Urbana], University of Illinois System-University of Illinois System, Department of Physics and Astronomy [Stony Brook], Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), Flatiron Institute, Simons Foundation, Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China, University of Chinese Academy of Sciences [Beijing] (UCAS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Max Planck Institute for Chemical Physics of Solids (CPfS), Max-Planck-Gesellschaft, University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Department of Physics, Saint-Petersburg State University, Saint-Petersburg State University, Universität Zürich [Zürich] = University of Zurich (UZH), Théorie de la Matière Condensée, Laboratoire de physique de l'ENS - ENS Paris (LPENS), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), University of Zurich, Wieder, Benjamin J, Bernevig, B Andrei, Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
Subjects: Electronic structure, 530 Physics, Chemical physics, FOS: Physical sciences, 02 engineering and technology, Crystal structure, 10192 Physics Institute, Topology, 01 natural sciences, Quantum chemistry, Characterization and analytical techniques, Coatings and Films, Biomaterials, symbols.namesake, Electronic and spintronic devices, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Chemistry, Electronic, Topological insulators, Optical and Magnetic Materials, 010306 general physics, Topology (chemistry), 2505 Materials Chemistry, ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Fermi level, 2502 Biomaterials, 2508 Surfaces, Coatings and Films, 2504 Electronic, Optical and Magnetic Materials, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Semimetal, Symmetry (physics), Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 2101 Energy (miscellaneous), Surfaces, Topological insulator, symbols, Condensed Matter::Strongly Correlated Electrons, 0210 nano-technology, Electronic materials, Energy (miscellaneous)
Abstract: Topological materials discovery has evolved at a rapid pace over the past 15 years following the identification of the first nonmagnetic topological insulators (TIs), topological crystalline insulators (TCIs), and 3D topological semimetals (TSMs). Most recently, through complete analyses of symmetry-allowed band structures - including the theory of Topological Quantum Chemistry (TQC) - researchers have determined crystal-symmetry-enhanced Wilson-loop and complete symmetry-based indicators for nonmagnetic topological phases, leading to the discovery of higher-order TCIs and TSMs. The recent application of TQC and related methods to high-throughput materials discovery has revealed that over half of all of the known stoichiometric, solid-state, nonmagnetic materials are topological at the Fermi level, over 85% of the known stoichiometric materials host energetically isolated topological bands, and that just under $2/3$ of the energetically isolated bands in known materials carry the stable topology of a TI or TCI. In this Review, we survey topological electronic materials discovery in nonmagnetic crystalline solids from the prediction of the first 2D and 3D TIs to the recently introduced methods that have facilitated large-scale searches for topological materials. We also discuss future venues for the identification and manipulation of solid-state topological phases, including charge-density-wave compounds, magnetic materials, and 2D few-layer devices., Comment: Final version, 27 pages, 7 figures
Published: 2021
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9. Quantum crystal structure in the 250-kelvin superconducting lanthanum hydride

Author: Ryotaro Arita, José A. Flores-Livas, Terumasa Tadano, Takashi Koretsune, Matteo Calandra, Francesco Mauri, Lorenzo Monacelli, Antonio Sanna, Raffaello Bianco, Francesco Belli, Ion Errea, European Commission, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Max-Planck-Institut für Mikrostrukturphysik (MPI-HALLE), Max-Planck-Gesellschaft, European Research Council, Ministerio de Economía y Competitividad (España), Ministry of Education, Culture, Sports, Science and Technology (Japan), and Swiss National Science Foundation
Subjects: High-pressure, Ab initio, FOS: Physical sciences, 02 engineering and technology, Crystal structure, 7. Clean energy, 01 natural sciences, Superconductivity (cond-mat.supr-con), Condensed Matter::Superconductivity, 0103 physical sciences, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, Quantum, Quantum fluctuation, [PHYS]Physics [physics], Physics, Superconductivity, Condensed Matter - Materials Science, Multidisciplinary, Condensed matter physics, superconductivity, Condensed Matter - Superconductivity, Hydrides, Materials Science (cond-mat.mtrl-sci), Energy landscape, Quantum effects, 021001 nanoscience & nanotechnology, Coupling (probability), High-temperature superconductivity, 0210 nano-technology, Ground state
Abstract: arXiv:1907.11916v1, The discovery of superconductivity at 200 kelvin in the hydrogen sulfide system at high pressures demonstrated the potential of hydrogen-rich materials as high-temperature superconductors. Recent theoretical predictions of rare-earth hydrides with hydrogen cages and the subsequent synthesis of LaH10 with a superconducting critical temperature (Tc) of 250 kelvin have placed these materials on the verge of achieving the long-standing goal of room-temperature superconductivity. Electrical and X-ray diffraction measurements have revealed a weakly pressure-dependent Tc for LaH10 between 137 and 218 gigapascals in a structure that has a face-centred cubic arrangement of lanthanum atoms. Here we show that quantum atomic fluctuations stabilize a highly symmetrical Fm3¯¯¯m crystal structure over this pressure range. The structure is consistent with experimental findings and has a very large electron–phonon coupling constant of 3.5. Although ab initio classical calculations predict that this Fm3¯¯¯m structure undergoes distortion at pressures below 230 gigapascals, yielding a complex energy landscape, the inclusion of quantum effects suggests that it is the true ground-state structure. The agreement between the calculated and experimental Tc values further indicates that this phase is responsible for the superconductivity observed at 250 kelvin. The relevance of quantum fluctuations calls into question many of the crystal structure predictions that have been made for hydrides within a classical approach and that currently guide the experimental quest for room-temperature superconductivity. Furthermore, we find that quantum effects are crucial for the stabilization of solids with high electron–phonon coupling constants that could otherwise be destabilized by the large electron–phonon interaction9, thus reducing the pressures required for their synthesis., This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 802533); the Spanish Ministry of Economy and Competitiveness (FIS2016-76617-P); Grant-in-Aid for Scientific Research (number 16H06345, 18K03442 and 19H05825) from the Ministry of Education, Culture, Sports, Science and Technology, Japan; and NCCR MARVEL funded by the Swiss National Science Foundation. Computational resources were provided by the Barcelona Superconducting Center (project FI-2019-1-0031) and the Swiss National Supercomputing Center (CSCS) with project s970.
Published: 2020
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10. Double Rabi Splitting in a Strongly Coupled System of Core–Shell Au@Ag Nanorods and J-Aggregates of Multiple Fluorophores

Author: Ana Sánchez-Iglesias, Luis M. Liz-Marzán, Dzmitry Melnikau, Yury P. Rakovich, Alexander A. Govyadinov, Marek Grzelczak, Igor Nabiev, CICNanoGUNE, Carbon Bionanotechnology Laboratory (CICbiomaGUNE), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Laboratoire de Recherche en Nanosciences - EA 4682 (LRN), SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Ministry of Education and Science of the Russian Federation, Eusko Jaurlaritza, Melnikau, D. [0000-0002-6588-8122], Grzelczak, Marek [0000-0002-3458-8450], Nabiev, Igor [0000-0002-8391-040X], Liz-Marzán, Luis Manuel [0000-0002-6647-1353], Rakovich, Yury P. [0000-0003-0111-2920], Melnikau, D., Grzelczak, Marek, Nabiev, Igor, Liz-Marzán, Luis Manuel, and Rakovich, Yury P.
Subjects: Strongly coupled, Multi-mode optical fiber, Materials science, Energy transfer, Physics::Optics, macromolecular substances, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 7. Clean energy, Molecular physics, 0104 chemical sciences, Core shell, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Strong coupling, General Materials Science, Nanorod, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Physical and Theoretical Chemistry, 0210 nano-technology, J-aggregate, ComputingMilieux_MISCELLANEOUS
Abstract: The interaction of several components in the strong coupling regime yielding multiple Rabi splittings opens up remarkable possibilities for studies of multimode hybridization and energy transfer, which is of considerable interest in both fundamental and applied science. Here we demonstrate that three different components, such as core−shell Au@Ag nanorods and J-aggregates of two different dyes, can be integrated into a single hybrid structure, which leads to strong collective exciton− plasmon coupling and double-mode Rabi splitting totaling 338 meV. We demonstrate strong coupling in these multicomponent plexitonic nanostructures by means of magnetic circular dichroism spectroscopy and demonstrate strong magneto-optical activity for the three hybridized states resulting from this coupling. The J-aggregates of two different nonmagnetic dyes interact with metal nanoparticles effectively, achieving magnetic properties due to the hybridization of electronic excitations in the threecomponent system., This work was supported by MINECO (Ministerio de Economiá y Competitividad), Spain, Projects FIS2016-80174-P (PLASMOQUANTA) and MAT2017-86659-R (MULTIMAGE). I.R.N. and Y.P.R. acknowledge support from the Ministry of Education and Science of the Russian Federation under Grant No. 14.Y26.31.0011 and funding from the Basque Government (Grant No. IT1164-19). This work was coordinated under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720).
Published: 2019
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11. Light in correlated disordered media

Author: VYNCK, Kevin, PIERRAT, Romain, CARMINATI, Rémi, FROUFE-PÉREZ, Luis S., SCHEFFOLD, Frank, SAPIENZA, Riccardo, VIGNOLINI, Silvia, SÁENZ, Juan José, Laboratoire Photonique, Numérique et Nanosciences (LP2N), Université de Bordeaux (UB)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), Modélisation de la matière condensée et des interfaces (MMCI), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Department of Physics [Fribourg], Université de Fribourg = University of Fribourg (UNIFR), Blackett Laboratory, Imperial College London, Department of Chemistry [Cambridge, UK], University of Cambridge [UK] (CAM), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Swiss National Science Foundation through project numbers 169074, 188494 and 197146, EPSRC, ANR-16-CE30-0008,NanoMiX,Nanophotonique des milieux complexes : nouveaux outils de modélisation vers de nouveaux phénomènes optiques(2016), ANR-19-CE09-0014,NANO-APPEARANCE,Surfaces nanostructurées complexes pour la conception de l'apparence visuelle(2019), ANR-10-LABX-0024,WIFI,Institut Langevin : Ondes et Images, du Fondamental à l'Innovation(2010), ANR-10-IDEX-0001,PSL,Paris Sciences et Lettres(2010), European Project: 639088,H2020,ERC-2014-STG,SeSaMe(2015), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), University of Fribourg, and Basque Foundation for Science (Ikerbasque)
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Condensed Matter - Mesoscale and Nanoscale Physics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Soft Condensed Matter (cond-mat.soft), FOS: Physical sciences, Physics::Optics, Disordered Systems and Neural Networks (cond-mat.dis-nn), Condensed Matter - Disordered Systems and Neural Networks, Condensed Matter - Soft Condensed Matter, Optics (physics.optics), Physics - Optics
Abstract: The optics of correlated disordered media is a fascinating research topic emerging at the interface between the physics of waves in complex media and nanophotonics. Inspired by photonic structures in nature and enabled by advances in nanofabrication processes, recent investigations have unveiled how the design of structural correlations down to the subwavelength scale could be exploited to control the scattering, transport and localization of light in matter. From optical transparency to superdiffusive light transport to photonic gaps, the optics of correlated disordered media challenges our physical intuition and offers new perspectives for applications. This article reviews the theoretical foundations, state-of-the-art experimental techniques and major achievements in the study of light interaction with correlated disorder, covering a wide range of systems -- from short-range correlated photonic liquids, to L\'evy glasses containing fractal heterogeneities, to hyperuniform disordered photonic materials. The mechanisms underlying light scattering and transport phenomena are elucidated on the basis of rigorous theoretical arguments. We overview the exciting ongoing research on mesoscopic phenomena, such as transport phase transitions and speckle statistics, and the current development of disorder engineering for applications such as light-energy management and visual appearance design. Special efforts are finally made to identify the main theoretical and experimental challenges to address in the near future., Comment: Submitted to Reviews of Modern Physics. Feedbacks are welcome
Published: 2021

12. Translational Inelasticity of Hydrogen Atoms Scattering off Hydrogen-Covered W(110) Surfaces

Author: L. Uranga-Piña, Aliezer Martínez Mesa, C. Crespos, Oihana Galparsoro, Pascal Larrégaray, Raidel Martin Barrios, University of Havana (Universidad de la Habana) (UH), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Universidad de La Habana [Cuba], Institut des Sciences Moléculaires (ISM), and Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Hydrogen, Scattering, chemistry.chemical_element, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, General Energy, chemistry, 0103 physical sciences, Physical and Theoretical Chemistry, 010306 general physics, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2021
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13. All Topological Bands of All Nonmagnetic Stoichiometric Materials

Author: Maia G. Vergniory, Benjamin J. Wieder, Luis Elcoro, Stuart S. P. Parkin, Claudia Felser, B. Andrei Bernevig, Nicolas Regnault, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Max Planck Institute for Chemical Physics of Solids (CPfS), Max-Planck-Gesellschaft, Department of Physics [MIT Cambridge], Massachusetts Institute of Technology (MIT), Department of Physics, Northeastern University, Northeastern University [Boston], Department of Physics, Princeton University (DPPU), Princeton University, University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Max Planck Institute of Microstructure Physics, Théorie de la Matière Condensée, Laboratoire de physique de l'ENS - ENS Paris (LPENS), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), and European Project: 742068 ,TOP-MAT
Subjects: [PHYS]Physics [physics], Condensed Matter - Materials Science, Multidisciplinary, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences
Abstract: Topological Quantum Chemistry and Symmetry-Based Indicators have facilitated large-scale searches for materials with topological properties at the Fermi energy ($E_{F}$). We report the completion of a publicly accessible catalog of stable and fragile topology in all of the bands both at and away from $E_{F}$ in the 96,196 processable entries in the Inorganic Crystal Structure Database. Our calculations represent the completion of the symmetry-indicated band topology of known nonmagnetic materials, and enable the discovery of repeat-topological and supertopological materials, which include rhombohedral bismuth and Bi$_2$Mg$_3$. We find that 52.65% of all materials are topological at $E_{F}$, roughly $2/3$ of bands across all materials exhibit symmetry-indicated stable topology, and that 87.99% of all materials contain at least one stable or fragile topological band., 212 pages, 108 figures, 34 tables. Final version. The Topological Materials Database is available either at the website https://www.topologicalquantumchemistry.com or its mirror https://www.topologicalquantumchemistry.fr
Published: 2021
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14. Many-Body Physics in Small Systems: Observing the Onset and Saturation of Correlation in Linear Atomic Chains

Author: Garnett W. Bryant, Tomáš Neuman, Alex Debrecht, Javier Aizpurua, Emily Townsend, National Institute of Standards and Technology [Gaithersburg] (NIST), University of Maryland [Baltimore], Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), University of Rochester [USA], Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), and univOAK, Archive ouverte
Subjects: Physics, [PHYS.NUCL] Physics [physics]/Nuclear Theory [nucl-th], Condensed Matter - Mesoscale and Nanoscale Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Diagonalizable matrix, Complex system, Physical system, FOS: Physical sciences, 02 engineering and technology, Electron, 021001 nanoscience & nanotechnology, 01 natural sciences, Article, 3. Good health, Quantum mechanics, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Coulomb, 010306 general physics, 0210 nano-technology, Ground state, Quantum, Eigenvalues and eigenvectors
Abstract: The exact study of small systems can guide us toward relevant measures for extracting information about many-body physics as we move to larger and more complex systems capable of quantum information processing or quantum analog simulation. We use exact diagonalization to study many electrons in short one-dimensional atom chains represented by long-range extended Hubbard-like models. We introduce a measure, the single-particle excitation content (SPEC) of an eigenstate and show that the functional dependence of the SPEC on the eigenstate number reveals the nature of the ground state (ordered phases), and the onset and saturation of correlation between the electrons as Coulomb interaction strength increases. We use this SPEC behavior to identify five regimes as interaction is increased: A noninteracting single-particle regime, a regime of perturbative Coulomb interaction in which the SPEC is a nearly universal function of eigenstate number, the onset and saturation of correlation, a regime of fully correlated states in which hopping is a perturbation, and the SPEC is a different universal function of state number and the regime of no hopping. In particular, the behavior of the SPEC shows that when electron-electron correlation plays a minor role, all of the lowest-energy eigenstates are made up primarily of single-particle excitations of the ground state, and as the Coulomb interaction increases, the lowest-energy eigenstates increasingly contain many-particle excitations. In addition, the SPEC highlights a fundamental distinct difference between a noninteracting system and one with minute very weak interactions. Although the SPEC is a quantity that can be calculated for small exactly diagonalizable systems, it guides our intuition for larger systems, suggesting the nature of excitations and their distribution in the spectrum. Thus, this function, such as correlation functions or order parameters, provides us with a window of intuition about the behavior of a physical system.
Published: 2021
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15. Superconducting Scanning Tunneling Microscope Tip to Reveal Sub-millielectronvolt Magnetic Energy Variations on Surfaces

Author: L. Garnier, Deung-Jang Choi, Roberto Robles, Nicolás Lorente, Laurent Limot, Cristina Mier, Benjamin Verlhac, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Agence Nationale de la Recherche (France), European Commission, Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and limot, laurent
Subjects: [PHYS]Physics [physics], Superconductivity, Materials science, Magnetic energy, Resolution (electron density), Conductance, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, [PHYS] Physics [physics], 3. Good health, law.invention, Molecular geometry, law, 0103 physical sciences, General Materials Science, Physical and Theoretical Chemistry, Scanning tunneling microscope, 010306 general physics, 0210 nano-technology, Excitation, Spin-½
Abstract: Combining the complex ordering ability of molecules with their local magnetic properties is a little-explored technique to tailor spin structures on surfaces. However, revealing the molecular geometry can be demanding. Nickelocene (Nc) molecules present a large spin-flip excitation leading to clear changes of conductance at the excitation-threshold bias. Using a superconducting tip, we have the energy resolution to detect small shifts of the Nc spin-flip excitation thresholds, permitting us to reveal the different individual environments of Nc molecules in an ordered layer. This knowledge allows us to reveal the adsorption configuration of a complex molecular structure formed by Nc molecules in different orientations and positions. As a consequence, we infer that Nc layers present a strong noncollinear magnetic-moment arrangement., Financial support from the Spanish MICINN (project RTI2018-097895-B-C44), the European H2020 FET open project MeMo (grant no. 766864), and the French Agence Nationale de la Recherche (grants no. ANR-13-BS10-0016, ANR-11-LABX-0058 NIE and ANR-10-LABX-0026 CSC) is gratefully acknowledged.
Published: 2021
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16. Ultrafast dynamics of electronic resonances in molecules adsorbed on metal surfaces: a wave packet propagation approach

Author: Andrey G. Borisov, Fernando Aguilar-Galindo, Sergio Díaz-Tendero, UAM. Departamento de Química, Departmento de Quimica, Universidad Autonoma de Madrid, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Nanophysique et Surfaces, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Condensed Matter Physics Center (IFIMAC), Institute for Advanced Research in Chemical Science (IAdChem) (IAdChem), Universidad Autonoma de Madrid (UAM), and Centro de Computacion Cientifica at the Universidad Autonoma de Madrid (CCC-UAM)Red Española de Supercomputacion (RES)MICINN - Spanish Ministry of Science and Innovation - projects CTQ2016-76061-P and PID2019-110091GBI00'Maria de Maeztu' (CEX2018-000805-M) Program for Centers of Excellence in R&D
Subjects: Materials science, Population, Schrödinger equation, Electronic structure, Electron, WPP, 01 natural sciences, Molecular physics, Electron transfer, Atomic orbital, Metal surfaces, 0103 physical sciences, Molecular orbital, Physical and Theoretical Chemistry, education, education.field_of_study, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], 010304 chemical physics, Química, Computer Science Applications, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Coupled cluster, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Density functional theory, Photoemission, RCT
Abstract: We present a wave packet propagation-based method to study the electron dynamics in molecular species in the gas phase and adsorbed on metal surfaces. It is a very general method that can be employed to any system where the electron dynamics is dominated by an active electron and the coupling between the discrete and continuum electronic states is of importance. As an example, one can consider resonant molecule-surface electron transfer or molecular photoionization. Our approach is based on a computational strategy allowing incorporating ab initio inputs from quantum chemistry methods, such as density functional theory, Hartree-Fock, and coupled cluster. Thus, the electronic structure of the molecule is fully taken into account. The electron wave function is represented on a three-dimensional grid in spatial coordinates, and its temporal evolution is obtained from the solution of the time-dependent Schrödinger equation. We illustrate our method with an example of the electron dynamics of anionic states localized on organic molecules adsorbed on metal surfaces. In particular, we study resonant charge transfer from the I orbitals of three vinyl derivatives (acrylamide, acrylonitrile, and acrolein) adsorbed on a Cu(100) surface. Electron transfer between these lowest unoccupied molecular orbitals and the metal surface is extremely fast, leading to a decay of the population of the molecular anion on the femtosecond timescale. We detail how to analyze the time-dependent electronic wave function in order to obtain the relevant information on the system: The energies and lifetimes of the molecule-localized quasistationary states, their resonant wavefunctions, and the population decay channels. In particular, we demonstrate the effect of the electronic structure of the substrate on the energy and momentum distribution of the hot electrons injected into the metal by the decaying molecular resonance, This work was partially supported by the MICINN-Spanish Ministry of Science and Innovation-projects CTQ2016-76061-P and PID2019-110091GBI00 and the “María de Maeztu” (CEX2018-000805-M) Program for Centers of Excellence in R&D
Published: 2021
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17. van der Waals driven anharmonic melting of the 3D charge density wave in $VSe_{2}$

Author: Sanjoy K. Mahatha, Kai Rossnagel, Santiago Blanco-Canosa, Josu Diego, Francesco Mauri, Lorenzo Monacelli, Raffaello Bianco, Ayman Said, Matteo Calandra, Ion Errea, Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Argonne National Laboratory [Lemont] (ANL), Deutsches Elektronen-Synchrotron [Hamburg] (DESY), Dipartimento di Fisica [Roma La Sapienza], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Università degli Studi di Trento (UNITN), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Christian-Albrechts-Universität zu Kiel (CAU), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Ministero dell'Istruzione, dell'Università e della Ricerca, Agence Nationale de la Recherche (France), Department of Energy (US), European Commission, and Argonne National Laboratory (US)
Subjects: Electronic properties and materials, Science, General Physics and Astronomy, CDW, 02 engineering and technology, Soft modes, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, symbols.namesake, Condensed Matter::Superconductivity, 0103 physical sciences, Wave vector, 010306 general physics, [PHYS]Physics [physics], Physics, Superconductivity, Multidisciplinary, Condensed matter physics, Scattering, Anharmonicity, General Chemistry, 021001 nanoscience & nanotechnology, Brillouin zone, Phase transitions and critical phenomena, symbols, Condensed Matter::Strongly Correlated Electrons, ddc:500, van der Waals force, 0210 nano-technology, Charge density wave
Abstract: Nature Communications 12(1), 598 (1-7) (2021). doi:10.1038/s41467-020-20829-2, Understanding of charge-density wave (CDW) phases is a main challenge in condensed matter due to their presence in high-Tc superconductors or transition metal dichalcogenides (TMDs). Among TMDs, the origin of the CDW in VSe$_2$ remains highly debated. Here, by means of inelastic x-ray scattering and first-principles calculations, we show that the CDW transition is driven by the collapse at 110 K of an acoustic mode at q$_{CDW}$ = (2.25 0 0.7) r.l.u. The softening starts below 225 K and expands over a wide region of the Brillouin zone, identifying the electron-phonon interaction as the driving force of the CDW. This is supported by our calculations that determine a large momentum-dependence of the electron-phonon matrix-elements that peak at the CDW wave vector. Our first-principles anharmonic calculations reproduce the temperature dependence of the soft mode and the T$_{CDW}$ onset only when considering the out-of-plane van der Waals interactions, which reveal crucial for the melting of the CDW phase., Published by Nature Publishing Group UK, [London]
Published: 2021
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18. Siesta : recent developments and applications

Author: Rafi Ullah, Georg Huhs, Emanuele Bosoni, Volker Blum, Alberto García, Pablo Ordejón, Emilio Artacho, Andrei Postnikov, Irina V. Lebedeva, Fabiano Corsetti, Richard Korytár, Miguel Pruneda, Ramón Cuadrado, Vladimir Dikan, Roberto Robles, Pablo García-Fernández, Jaime Ferrer, Mads Brandbyge, Javier Junquera, Jorge Cerdá, José M. Soler, Pedro Brandimarte, Nick Rübner Papior, Lin Lin, Victor Yu, Stephan Mohr, Sandra García, Sergio Illera, Peter Koval, Víctor M. García-Suárez, Arsalan Akhtar, Yann Pouillon, Pablo López-Tarifa, Sara G. Mayo, Julian D. Gale, Daniel Sánchez-Portal, Barcelona Supercomputing Center, Facultad de Ciencias y Tecnologías Químicas de Ciudad Real (UCLM), Institut Català de Nanociència i Nanotecnologia (ICN2), Universitat Autònoma de Barcelona (UAB), Catalan Institute of Nanoscience and Nanotechnology (ICN2), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Barcelona Institute of Science and Technology (BIST), Department of Earth Sciences [Cambridge, UK], University of Cambridge [UK] (CAM), Duke University [Durham], Institut de Ciència de Materials de Barcelona (ICMAB), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Center for Nanostructured Graphene, Instituto Ciencias del Mar, CICNanoGUNE, University of Oviedo, Nanochemistry Research Institute, Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC), Universidad de Cantabria [Santander], Universidad de Oviedo [Oviedo], Institut des Biomolécules Max Mousseron [Pôle Chimie Balard] (IBMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Barcelona Supercomputing Center - Centro Nacional de Supercomputacion (BSC - CNS), Department of Applied Mathematics and Institute of Theoretical Computer Science (Charles University), Charles University [Prague] (CU), CIC NanoGUNE BRTA, Shanghai Inst Biol Sci, Inst Plant Physiol & Ecol, Natl Key Lab Plant Mol Genet, Chinese Academy of Sciences [Beijing] (CAS), Ecole Polytechnique Fédérale de Lausanne (EPFL), Universidad Autonoma de Madrid (UAM), University of Basel (Unibas), Laboratoire de Chimie et Physique - Approche Multi-échelle des Milieux Complexes (LCP-A2MC), Université de Lorraine (UL), ICN2 - Institut Catala de Nanociencia i Nanotecnologia (ICN2), Centro Mixto CSIC-UPV/EHU, Donostia International Physics Center - DIPC (SPAIN), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Departamento de Ciencias de la Tierra y Fisica de la Materia Condensada, Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Generalitat de Catalunya, European Commission, Universidad del País Vasco, Eusko Jaurlaritza, National Science Foundation (US), Universidad de Cantabria, and Simune Atomistics
Subjects: Scheme (programming language), Interface (Java), Computer science, Wannier functions, [PHYS.MPHY]Physics [physics]/Mathematical Physics [math-ph], Interoperability, FOS: Physical sciences, General Physics and Astronomy, Molecular dynamics, 010402 general chemistry, computer.software_genre, 01 natural sciences, Electronic Structure Software, Computational science, Informàtica::Aplicacions de la informàtica [Àrees temàtiques de la UPC], Ab initio electronic structure calculations, Matrix analytic methods, 0103 physical sciences, Spin-orbit interactions, Plug-in, Dinàmica molecular, Multiscale methods, Charge density, Density functional theory (DFT)+U, Physical and Theoretical Chemistry, SIESTA (computer program), Electronic Structure Library, computer.programming_language, Ballistic electron transport, Condensed Matter - Materials Science, Mathematical models, 010304 chemical physics, SIESTA, Electron transport, Hybrid density functional calculations, Materials Science (cond-mat.mtrl-sci), Models matemàtics, Computational Physics (physics.comp-ph), Grid, Supercomputer, Pseudopotential method, PSeudopotential Markup Language, 0104 chemical sciences, Time dependent density functional theory, Workflow, Density functional theory, High performance computing, Physics - Computational Physics, computer
Abstract: This article is part of the JCP Special Topic on Electronic Structure Software., A review of the present status, recent enhancements, and applicability of the SIESTA program is presented. Since its debut in the mid-1990s, SIESTA’s flexibility, efficiency, and free distribution have given advanced materials simulation capabilities to many groups worldwide. The core methodological scheme of SIESTA combines finite-support pseudo-atomic orbitals as basis sets, norm-conserving pseudopotentials, and a realspace grid for the representation of charge density and potentials and the computation of their associated matrix elements. Here, we describe the more recent implementations on top of that core scheme, which include full spin–orbit interaction, non-repeated and multiple-contact ballistic electron transport, density functional theory (DFT)+U and hybrid functionals, time-dependent DFT, novel reduced-scaling solvers, density-functional perturbation theory, efficient van der Waals non-local density functionals, and enhanced molecular-dynamics options. In addition, a substantial effort has been made in enhancing interoperability and interfacing with other codes and utilities, such as WANNIER90 and the second-principles modeling it can be used for, an AiiDA plugin for workflow automatization, interface to Lua for steering SIESTA runs, and various post-processing utilities. SIESTA has also been engaged in the Electronic Structure Library effort from its inception, which has allowed the sharing of various low-level libraries, as well as data standards and support for them, particularly the PSeudopotential Markup Language definition and library for transferable pseudopotentials, and the interface to the ELectronic Structure Infrastructure library of solvers. Code sharing is made easier by the new open-source licensing model of the program. This review also presents examples of application of the capabilities of the code, as well as a view of on-going and future developments., Siesta development was historically supported by different Spanish National Plan projects (Project Nos. MEC-DGES-PB95-0202, MCyT-BFM2000-1312, MEC-BFM2003-03372, FIS2006-12117, FIS2009-12721, FIS2012-37549, FIS2015-64886-P, and RTC-2016-5681-7), the latter one together with Simune Atomistics Ltd. We are thankful for financial support from the Spanish Ministry of Science, Innovation and Universities through Grant No. PGC2018-096955-B. We acknowledge the Severo Ochoa Center of Excellence Program [Grant Nos. SEV-2015-0496 (ICMAB) and SEV-2017-0706 (ICN2)], the GenCat (Grant No. 2017SGR1506), and the European Union MaX Center of Excellence (EU-H2020 Grant No. 824143). P.G.-F. acknowledges support from Ramón y Cajal (Grant No. RyC-2013-12515). J.I.C. acknowledges Grant No. RTI2018-097895-B-C41. R.C. acknowledges the European Union’s Horizon 2020 Research and Innovation Program under Marie Skłodoswka-Curie Grant Agreement No. 665919. D.S.P, P.K., and P.B. acknowledge Grant No. MAT2016-78293-C6, FET-Open No. 863098, and UPV-EHU Grant No. IT1246-19. V. W. Yu was supported by a MolSSI Fellowship (U.S. NSF Award No. 1547580), and V.B. and V.W.Y. were supported by the ELSI Development by the NSF (Award No. 1450280).
Published: 2021
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19. Correlation between the dynamics of nanoconfined water and the local chemical environment in calcium silicate hydrate nanominerals

Author: Cyril Aymonier, Jorge S. Dolado, Guido Goracci, Paula Sanz Camacho, Valentina Musumeci, Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), BASKRETE-Euskampus Fundazioa, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), This research was carried out under the umbrella of the Bordeaux-Euskampus Euro-regional Campus of International Excellence initiative and supported by the International Doctoral Program developed between the University of Bordeaux (UB) and the University of the Basque Country (UPV/EHU). Valentina Musumeci is grateful to the Initiative of Excellence (IdEX) of the University of Bordeaux for financial support. The authors also acknowledge CNRS, Bordeaux INP and Région Nouvelle-Aquitaine for their financial support. This work is partially supported by the Gobierno Vasco-UPV/EHU project IT1246-19 and the Spanish Ministry of Science, Innovation and Universities projects PCI2019-103657 and RTI2018-098554-B-I00., Eusko Jaurlaritza, Universidad del País Vasco, Université de Bordeaux, Centre National de la Recherche Scientifique (France), Région Nouvelle-Aquitaine, Ministerio de Ciencia, Innovación y Universidades (España), and Agencia Estatal de Investigación (España)
Subjects: Dielectric spectroscopy, Chemical environment, 010402 general chemistry, 01 natural sciences, Catalysis, Hydrothermal circulation, chemistry.chemical_compound, 0103 physical sciences, Molecule, Humans, Calcium silicate hydrate, Minerals, Supercritical fluids, 010304 chemical physics, 010405 organic chemistry, Silicates, Organic Chemistry, Relaxation (NMR), Solvation, Water, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, Calcium Compounds, Supercritical fluid, 0104 chemical sciences, Calcium silicate, Nanocrystal, chemistry, Chemical engineering, Nanoconfined water, Nanominerals
Abstract: Calcium silicate hydrates are members of a large family of minerals with layered structures containing pendant CaOH and SiOH groups that interact with confined water molecules. To rationalize the impact of the local chemical environment on the dynamics of water, SiOH- and CaOH-rich model nanocrystals were synthesized by using the continuous supercritical hydrothermal method and then systematically studied by a combination of spectroscopic techniques. In our comprehensive analysis, the ultrafast relaxation dynamics of hanging hydroxy groups can be univocally assigned to CaOH or SiOH environments, and the local chemical environment largely affects the H-bond network of the solvation water. Interestingly, the ordered “ice-like” solvation water found in the SiOH-rich environments is converted to a disordered “liquid-like” distribution in the CaOH-rich environment. This refined picture of the dynamics of confined water and hydroxy groups in calcium silicate hydrates can also be applied to other water-containing materials, with a significant impact in many fields of materials science., This research was carried out under the umbrella of the Bordeaux-Euskampus Euro-regional Campus of International Excellence initiative and supported by the International Doctoral Program developed between the University of Bordeaux (UB) and the University of the Basque Country (UPV/EHU). Valentina Musumeci is grateful to the Initiative of Excellence (IdEX) of the University of Bordeaux for financial support. The authors also acknowledge CNRS, Bordeaux INP and Région Nouvelle-Aquitaine for their financial support. This work is partially supported by the Gobierno Vasco-UPV/EHU project IT1246-19 and the Spanish Ministry of Science, Innovation and Universities projects PCI2019-103657 and RTI2018-098554-B-I00.
Published: 2021
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20. Data Management Plans:the Importance of Data Management in the BIG‐MAP Project

Author: Isidora Cekic-Laskovic, Frédéric Le Cras, Alexis Grimaud, Lukas Königer, Martin Winter, Eibar Flores, Leszek Niedzicki, Simon Clark, Helge S. Stein, Arghya Bhowmik, Hanne Lauritzen, Laurence J. Hardwick, Hongjiao Li, Robert Dominko, Martin Uhrin, Henning Lorrmann, Nicola Marzari, Karin Vels Hansen, Tejs Vegge, Giovanni Pizzi, Christian Wölke, Ivano E. Castelli, Daniel J. Arismendi-Arrieta, Karina Ulvskov Frederiksen, Fuzhan Rahmanian, Jackson Flowers, Sandrine Lyonnard, Jesper Friis, Wolfgang Wenzel, Kersti Hermansson, Danmarks Tekniske Universitet = Technical University of Denmark (DTU), Department of Materials Chemistry - The Angstrom Laboratory, Uppsala University, Helmholtz-Institute Münster (IEK-12), SINTEF Technology and Society, Stiftelsen for INdustriell og TEknisk Forskning Digital [Trondheim] (SINTEF Digital), National Institute of Chemistry, Helmholtz Institute Ulm (HIU), Chimie du solide et de l'énergie (CSE), Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Stephenson Institute for Renewable Energy, University of Liverpool, Fraunhofer Institute for Silicate Research (Fraunhofer ISC), Fraunhofer (Fraunhofer-Gesellschaft), Département de l'électricité et de l'hydrogène dans les transports (DEHT), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Karlsruhe Institute of Technology (KIT), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Theory and Simulation of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL), Faculty of Chemistry [Warsaw], University of Warsaw (UW), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Westfälische Wilhelms-Universität Münster = University of Münster (WWU), European Project: 957213 ,BATTERY 2030PLUS, European Project: 957189,BIG-MAP, Technical University of Denmark [Lyngby] (DTU), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de L'Energie Solaire (INES), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and University of Münster
Subjects: [SPI.OTHER]Engineering Sciences [physics]/Other, Technology, Computer and Information Sciences, batteries, databases, Process (engineering), Computer science, Data management, [INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS], Interoperability, FOS: Physical sciences, Energy Engineering and Power Technology, 02 engineering and technology, Plan (drawing), 010402 general chemistry, 01 natural sciences, data management plan, fair data, Batteries, Databases, Electrochemistry, Electrical and Electronic Engineering, data curation, Condensed Matter - Materials Science, FAIR data, Data curation, business.industry, Data management plan, Materials Science (cond-mat.mtrl-sci), Data- och informationsvetenskap, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Data flow diagram, Engineering management, Key (cryptography), ddc:620, 0210 nano-technology, business, ddc:600
Abstract: Open access to research data is increasingly important for accelerating research. Grant authorities therefore request detailed plans for how data is managed in the projects they finance. We have recently developed such a plan for the EU-H2020 BIG-MAP project - a cross-disciplinary project targeting disruptive battery-material discoveries. Essential for reaching the goal is extensive sharing of research data across scales, disciplines and stakeholders, not limited to BIG-MAP and the European BATTERY 2030+ initiative but within the entire battery community. The key challenges faced in developing the data management plan for such a large and complex project were to generate an overview of the enormous amount of data that will be produced, to build an understanding of the data flow within the project and to agree on a roadmap for making all data FAIR. This paper describes the process we followed and how we structured the plan., 12 pages, 4 figures; the full DMP is published as Supporting Information
Published: 2021
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21. Strong increase in the effective two-photon absorption cross-section of excitons in quantum dots due to the nonlinear interaction with localized plasmons in gold nanorods

Author: Yury P. Rakovich, Victor Krivenkov, Pavel Samokhvalov, Ana Sánchez-Iglesias, Igor Nabiev, Marek Grzelczak, The National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) [Moscow, Russia], CIC BiomaGUNE, CIC BiomaGUNE [Espagne], Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Laboratoire de Recherche en Nanosciences - EA 4682 (LRN), SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV), Ikerbasque - Basque Foundation for Science, Russian Science Foundation, Ministry of Education and Science of the Russian Federation, Eusko Jaurlaritza, Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Université de Reims Champagne-Ardenne, and Ministre de l'Enseignement Supérieur, de la Recherche et de l'Innovation (France)
Subjects: Plasmonic nanoparticles, Photoluminescence, Materials science, business.industry, Exciton, 02 engineering and technology, Purcell effect, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Two-photon absorption, 3. Good health, 0104 chemical sciences, Quantum dot, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, General Materials Science, Nanorod, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 0210 nano-technology, business, Plasmon
Abstract: Excitons in semiconductor quantum dots (QDs) feature high values of the two-photon absorption cross-sections (TPACSs), enabling applications of two-photon-excited photoluminescence (TPE PL) of QDs in biosensing and nonlinear optoelectronics. However, efficient TPE PL of QDs requires high-intensity laser fields, which limits these applications. There are two possible ways to increase the TPE PL of QDs: by increasing their photoluminescence quantum yield (PLQY) or by further increasing the TPACS. Plasmonic nanoparticles (PNPs) may act as open nanocavities for increasing the PLQY via the Purcell effect, but this enhancement is strictly limited by the maximum possible PLQY value of 100%. Here we directly investigated the effect of PNPs on the effective TPACS of excitons in QDs. We have found that effective TPACS of excitons in a QD–PMMA thin film can be increased by a factor of up to 12 near the linearly excited gold nanorods (GNRs). Using gold nanospheres (GNSs), in which plasmons cannot be excited in the infrared range, as a control system, we have shown that, although both GNSs and GNRs increase the recombination rate of excitons, the TPACS is increased only in the case of GNRs. We believe that the observed effect of TPACS enhancement is a result of the nonlinear interaction of the plasmons in GNRs with excitons in QDs, which we have supported by numerical simulations. The results show the way to the rational design of the spectral features of plasmon–exciton hybrids for using them in biosensing and nonlinear optoelectronics., V. K. acknowledges support from the Russian Science Foundation (Grant No. 18-72-10143) for the part of the study related to the investigation of the effects of PNPs on the effective TPACS of excitons in QDs and numerical simulations of these effects. Support from the Ministry of Education and Science of the Russian Federation (Grant No. 14.Y26.31.0011) for the part of this study related to the synthesis and functionalisation of the QDs and engineering of hybrid QD-GNR materials is also acknowledged. Y. R. acknowledges the support from the Basque Government (grant no. IT1164-19). Y. R. and M. G. acknowledge the support from the Spanish MINECO (PID2019-111772RB-I00). I. N. acknowledges the Ministry of Higher Education, Research and Innovation of the French Republic and Université de Reims Champagne-Ardenne.
Published: 2021
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22. Strong correlation between bonding network and critical temperature in hydrogen-based superconductors

Author: Julia Contreras-García, Trinidad Novoa, Ion Errea, Francesco Belli, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Laboratoire de chimie théorique (LCT), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), European Commission, European Research Council, and Comisión Nacional de Investigación Científica y Tecnológica (Chile)
Subjects: Electronic properties and materials, Hydrogen, Science, FOS: Physical sciences, General Physics and Astronomy, chemistry.chemical_element, 02 engineering and technology, 01 natural sciences, Article, General Biochemistry, Genetics and Molecular Biology, Superconducting properties and materials, Superconductivity (cond-mat.supr-con), Theoretical physics, 0103 physical sciences, 010306 general physics, Physics, Superconductivity, Multidisciplinary, Horizon (archaeology), Condensed Matter - Superconductivity, superconductivity, European research, General Chemistry, 021001 nanoscience & nanotechnology, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], chemistry, hydrogen, 0210 nano-technology, electronic localization function
Abstract: By analyzing structural and electronic properties of more than a hundred predicted hydrogen-based superconductors, we determine that the capacity of creating an electronic bonding network between localized units is key to enhance the critical temperature in hydrogen-based superconductors. We define a magnitude named as the networking value, which correlates with the predicted critical temperature better than any other descriptor analyzed thus far. By classifying the studied compounds according to their bonding nature, we observe that such correlation is bonding-type independent, showing a broad scope and generality. Furthermore, combining the networking value with the hydrogen fraction in the system and the hydrogen contribution to the density of states at the Fermi level, we can predict the critical temperature of hydrogen-based compounds with an accuracy of about 60 K. Such correlation is useful to screen new superconducting compounds and offers a deeper understating of the chemical and physical properties of hydrogen-based superconductors, while setting clear paths for chemically engineering their critical temperatures., This research was supported by the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement No. 802533 and 810367). J.C.G. and T.N. acknowledge the “Programa de Cooperación Científica ECOS-CONICYT” (No. ECOS170045) for financial support.
Published: 2021
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23. Giant topological longitudinal circular photo-galvanic effect in the chiral multifold semimetal CoSi

Author: Oscar Pozo, Xiufeng Han, Kaustuv Manna, Adolfo G. Grushin, Eugene J. Mele, Johnpierre Paglione, Bing Xu, Zhuoliang Ni, F. de Juan, Claudia Felser, Liang Wu, Yu Shrike Zhang, Kefeng Wang, University of Pennsylvania [Philadelphia], University of Maryland [College Park], University of Maryland System, Massachusetts Institute of Technology (MIT), Max Planck Institute for Chemical Physics of Solids (CPfS), Max-Planck-Gesellschaft, Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), University of Freiburg [Freiburg], Théorie de la Matière Condensée (TMC), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), and University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)
Subjects: Photon, Nonlinear optics, Science, Physics::Optics, FOS: Physical sciences, General Physics and Astronomy, 02 engineering and technology, Electron, Photon energy, Topology, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Article, Condensed Matter::Materials Science, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Mid-infrared photonics, Topological insulators, 010306 general physics, Infrared spectroscopy, Circular polarization, [PHYS]Physics [physics], Physics, Photocurrent, Condensed Matter - Materials Science, Multidisciplinary, Condensed Matter - Mesoscale and Nanoscale Physics, Materials Science (cond-mat.mtrl-sci), General Chemistry, 021001 nanoscience & nanotechnology, Polarization (waves), Semimetal, Topological insulator, 0210 nano-technology, Physics - Optics, Optics (physics.optics)
Abstract: The absence of mirror symmetry, or chirality, is behind striking natural phenomena found in systems as diverse as DNA and crystalline solids. A remarkable example occurs when chiral semimetals with topologically protected band degeneracies are illuminated with circularly polarized light. Under the right conditions, the part of the generated photocurrent that switches sign upon reversal of the light’s polarization, known as the circular photo-galvanic effect, is predicted to depend only on fundamental constants. The conditions to observe quantization are non-universal, and depend on material parameters and the incident frequency. In this work, we perform terahertz emission spectroscopy with tunable photon energy from 0.2 –1.1 eV in the chiral topological semimetal CoSi. We identify a large longitudinal photocurrent peaked at 0.4 eV reaching ~550 μ A/V2, which is much larger than the photocurrent in any chiral crystal reported in the literature. Using first-principles calculations we establish that the peak originates only from topological band crossings, reaching 3.3 ± 0.3 in units of the quantization constant. Our calculations indicate that the quantized circular photo-galvanic effect is within reach in CoSi upon doping and increase of the hot-carrier lifetime. The large photo-conductivity suggests that topological semimetals could potentially be used as novel mid-infrared detectors., Quantized circular photogalvanic effect (CPGE) is predicted in chiral topological semimetals, but the experimental observation remains challenging. Here, Ni et al. observe a large topological longitudinal photocurrent in CoSi, which is much larger than the photocurrent in any other chiral crystals, indicating quantized CPGE within reach upon doping and increase of the hot-carrier lifetime.
Published: 2021
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24. Wave-particle duality of electrons with spin-momentum locking

Author: Bercioux, Dario, van den Berg, Tineke, Ferraro, Dario, Rech, Jérôme, Jonckheere, Thibaut, Martin, Thierry, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Dipartimento di Fisica, Università di Genova, Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), CPT - E6 Nanophysique, Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Spanish Ministerio de Cien-cia, Innovation y Universidades (MICINN) through the ProjectFIS2017-82804-P, and by the Transnational Common LaboratoryQuantum-ChemPhys, and Università degli studi di Genova = University of Genoa (UniGe)
Subjects: Condensed Matter - Other Condensed Matter, Condensed Matter - Mesoscale and Nanoscale Physics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), FOS: Physical sciences, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Other Condensed Matter (cond-mat.other)
Abstract: We investigate the effects of spin-momentum locking on the interference and diffraction patterns due to a double- or single-slit in an electronic \emph{Gedankenexperiment}. We show that the inclusion of the spin-degree-of-freedom, when coupled to the motion direction of the carrier -- a typical situation that occurs in systems with spin-orbit interaction -- leads to a modification of the interference and diffraction patterns that depend on the geometrical parameters of the system., Comment: 10 pages and 8 figures
Published: 2020
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25. Strong coupling effects in a plexciton system of gold nanostars and J-aggregates

Author: Ana Sánchez-Iglesias, Yury P. Rakovich, Dzmitry Melnikau, Igor Nabiev, Pavel Samokhvalov, Marek Grzelczak, Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), The National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) [Moscow, Russia], Basque Research and Technology Alliance (BRTA), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Laboratoire de Recherche en Nanosciences - EA 4682 (LRN), SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Ministerio de Economía y Competitividad (España), Ministry of Science and Higher Education of the Russian Federation, Eusko Jaurlaritza, Russian Science Foundation, and Université de Reims Champagne-Ardenne
Subjects: Plasmons, Luminescence, Materials science, Exciton, Biophysics, Physics::Optics, 02 engineering and technology, Purcell effect, 01 natural sciences, Biochemistry, J-aggregates, 0103 physical sciences, Spontaneous emission, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, Absorption (electromagnetic radiation), J-aggregate, Plasmon, Strong coupling, Scattering, Nanostars, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Chemical physics, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Nanoparticles, Excitons, 0210 nano-technology
Abstract: Strong exciton–plasmon interaction enables effective control of the photonic properties of hybrid organic–inorganic nanostructures encompassing light absorption, scattering and luminescence. Whereas the manifestations of light-matter interactions in the absorption and scattering are reasonably well understood their relation to the luminescence as well as luminescence properties themselves in strongly coupled plexcitonic hybrids is still largely underexplored especially for a system with a complex mechanism of hybridisation of states. Here we report on investigation of the interaction between localized and hybridized plasmons in gold nanostars and excitons in J-aggregates under ambient conditions. Our findings demonstrate the quality performance of the formed plexciton system with multiple hybridization channels in terms of the parameters of strong coupling, such as Rabi splitting (230 meV), coupling-strength-to-transition energy ratio (0.07), and cooperativity (2.03). The results of time-resolved experiments elucidate the observed enhanced spontaneous emission rate with regard to the Purcell effect, whose value was estimated from the extinction spectra of the strongly coupled plexciton system., Financial supports from Projects PID2019-111772RB-I00 of the Spanish MINECO and the Ministry of Science and Higher Education of the Russian Federation (Grant No. 14.Y26.31.0011) are acknowledged. Y. R. acknowledges the support from the Basque Government (grant no. IT1164-19). P.S. and I.N acknowledge support from the Russian Science Foundation (grant no. 21-79-30048) of the part of this work related to nanomaterials manufacturing and functionalisation. I.N. acknowledges support from the Université de Reims Champagne-Ardenne. A.S.-I. acknowledges the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720).
Published: 2022
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26. Exciton Interactions, Excimer Formation, and [2π+2π] Photodimerization in Nonconjugated Curcuminoid‐BF 2 Dimers

Author: Olatz Uranga-Barandiaran, Frédéric Castet, Anthony D'Aléo, Elena Zaborova, Manon Catherin, David Casanova, Arnaud Brosseau, Gabriel Canard, Rémi Métivier, Frédéric Fages, Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Aix Marseille Université (AMU), Université de Bordeaux (UB), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Euskal Herriko Unibertsitatea [Guipúzcoa] (EHU), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Ecole Normale Supérieure Paris-Saclay (ENS Paris Saclay), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), MINECO/FEDER of the Spanish Government, ANR-10-IDEX-0003,IDEX BORDEAUX,Initiative d'excellence de l'Université de Bordeaux(2010), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Absorption spectroscopy, 010405 organic chemistry, Chemistry, Exciton, Organic Chemistry, aggregation, General Chemistry, Chromophore, 010402 general chemistry, Excimer, Photochemistry, photochromism, 01 natural sciences, Catalysis, 0104 chemical sciences, Folding (chemistry), excitonic coupling, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Photochromism, Intramolecular force, [CHIM]Chemical Sciences, Density functional theory, fluorescence, dyes/pigments
Abstract: International audience; We describe the synthesis of a series of covalently linked dimers of quadrupolar curcuminoid‐BF2 dyes and the detailed investigation of their solvent‐dependent spectroscopic and photophysical properties. In solvents of low polarity, intramolecular folding induces the formation of aggregated chromophores, the UV/Vis absorption spectra of which display the optical signature characteristic of weakly‐coupled H‐aggregates. The extent of folding and, in turn, of ground‐state aggregation is strongly dependent on the nature of the flexible linker. Steady‐state and time‐resolved fluorescence emission spectroscopies show that the Frenkel exciton relaxes into a fluorescent symmetrical excimer state with a long lifetime. Furthermore, our in‐depth studies show that a weakly emitting excimer lies on the pathway toward a photocyclomer. Two‐dimensional 1H NMR spectroscopy and density functional theory (DFT) allowed the structure of the photoproduct to be established. To our knowledge, this represents the first example of a [2π+2π] photodimerization of the curcuminoid chromophore.
Published: 2020
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27. Broad spectral tuning of ultra-low-loss polaritons in a van der Waals crystal by intercalation

Author: Qiaoliang Bao, Ion Errea, Jiahua Duan, Kyle Crowley, Javier Martín-Sánchez, Weiliang Ma, Halyna Volkova, Marta Autore, Ivan Prieto, Alexey Y. Nikitin, Javier Taboada-Gutiérrez, Andrei Bylinkin, Pablo Alonso-González, Rainer Hillenbrand, Kenta Kimura, Gonzalo Álvarez-Pérez, Shaojuan Li, Marie-Hélène Berger, Xuan P. A. Gao, Tsuyoshi Kimura, Principado de Asturias, Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Air Force Office of Scientific Research (US), Ministerio de Economía y Competitividad (España), Eusko Jaurlaritza, Australian Research Council, Ministerio de Economía, Industria y Competitividad (España), European Research Council, Institute of Science and Technology [Austria] (IST Austria), Centre des Matériaux (MAT), MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Graduate School of Engineering, Osaka University, Osaka University [Osaka], Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), CIC nanoGUNE Consolider, and Donostia International Physcis Center
Subjects: Materials science, Phonon, Intercalation (chemistry), Nanophotonics, Physics::Optics, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Molecular physics, Crystal, symbols.namesake, Condensed Matter::Materials Science, Condensed Matter::Superconductivity, Polariton, General Materials Science, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], business.industry, Mechanical Engineering, General Chemistry, Spectral bands, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Semiconductor, Mechanics of Materials, symbols, van der Waals force, 0210 nano-technology, business
Abstract: Phonon polaritons—light coupled to lattice vibrations—in polar van der Waals crystals are promising candidates for controlling the flow of energy on the nanoscale due to their strong field confinement, anisotropic propagation and ultra-long lifetime in the picosecond range1,2,3,4,5. However, the lack of tunability of their narrow and material-specific spectral range—the Reststrahlen band—severely limits their technological implementation. Here, we demonstrate that intercalation of Na atoms in the van der Waals semiconductor α-V2O5 enables a broad spectral shift of Reststrahlen bands, and that the phonon polaritons excited show ultra-low losses (lifetime of 4 ± 1 ps), similar to phonon polaritons in a non-intercalated crystal (lifetime of 6 ± 1 ps). We expect our intercalation method to be applicable to other van der Waals crystals, opening the door for the use of phonon polaritons in broad spectral bands in the mid-infrared domain., J.T.-G. and G.Á.-P. acknowledge support through the Severo Ochoa Program from the Government of the Principality of Asturias (nos. PA-18-PF-BP17-126 and PA-20-PF-BP19-053, respectively). J.M.-S. acknowledges finantial support from the Clarín Programme from the Government of the Principality of Asturias and a Marie Curie-COFUND grant (PA-18-ACB17-29) and the Ramón y Cajal Program from the Government of Spain (RYC2018-026196-I). K.C., X.P.A.G., H.V. and M.H.B. acknowledge the Air Force Office of Scientific Research (AFOSR) grant no. FA 9550-18-1-0030 for funding support. I.E. acknowledges financial support from the Spanish Ministry of Economy and Competitiveness (grant no. FIS2016-76617-P). A.Y.N. acknowledges the Spanish Ministry of Science, Innovation and Universities (national project no. MAT2017-88358-C3-3-R) and the Basque Government (grant no. IT1164-19). Q.B. acknowledges the support from Australian Research Council (grant nos. FT150100450, IH150100006 and CE170100039). R.H. acknowledges support from the Spanish Ministry of Economy, Industry, and Competitiveness (national project RTI2018-094830-B-100 and the Project MDM-2016-0618 of the María de Maeztu Units of Excellence Program) and the Basque Goverment (grant no. IT1164-19). P.A.-G. acknowledges support from the European Research Council under starting grant no. 715496, 2DNANOPTICA.
Published: 2020
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28. Linear and nonlinear optical responses in the chiral multifold semimetal RhSi

Author: Zhuoliang Ni, Adolfo G. Grushin, Jörn W. F. Venderbos, Kaustuv Manna, Liang Wu, Bing Xu, Christian Bernhard, Yu Shrike Zhang, F. de Juan, M. A. Sanchez-Martinez, Claudia Felser, University of Pennsylvania [Philadelphia], University of Fribourg, Théorie de la Matière Condensée (TMC), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Max Planck Institute for Chemical Physics of Solids (CPfS), Max-Planck-Gesellschaft, Massachusetts Institute of Technology (MIT), Drexel University, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), and University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)
Subjects: Terahertz radiation, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Optical conductivity, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Atomic physics. Constitution and properties of matter, 010306 general physics, Materials of engineering and construction. Mechanics of materials, [PHYS]Physics [physics], Physics, Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Nonlinear optics, Materials Science (cond-mat.mtrl-sci), Fermion, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Semimetal, 3. Good health, Electronic, Optical and Magnetic Materials, Brillouin zone, Topological insulator, TA401-492, Quasiparticle, 0210 nano-technology, Physics - Optics, QC170-197, Optics (physics.optics)
Abstract: Chiral topological semimetals are materials that break both inversion and mirror symmetries. They host interesting phenomena such as the quantized circular photogalvanic effect (CPGE) and the chiral magnetic effect. In this work, we report a comprehensive theoretical and experimental analysis of the linear and non-linear optical responses of the chiral topological semimetal RhSi, which is known to host multifold fermions. We show that the characteristic features of the optical conductivity, which display two distinct quasi-linear regimes above and below 0.4 eV, can be linked to excitations of different kinds of multifold fermions. The characteristic features of the CPGE, which displays a sign change at 0.4 eV and a large non-quantized response peak of around 160 $\mu \textrm{A V}^{-2}$ at 0.7 eV, are explained by assuming that the chemical potential crosses a flat hole band at the Brillouin zone center. Our theory predicts that, in order to observe a quantized CPGE in RhSi, it is necessary to increase the chemical potential as well as the quasiparticle lifetime. More broadly our methodology, especially the development of the broadband terahertz emission spectroscopy, could be widely applied to study photo-galvanic effects in noncentrosymmetric materials and in topological insulators in a contact-less way and accelerate the technological development of efficient infrared detectors based on topological semimetals., Comment: Accepted in npj Quantum Materials; Abstract updated
Published: 2020
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29. Propriétés spectrales et de transport de supraconducteurs à basse dimension en présence de champs dépendant du spin

Author: Baumard, Julie Isabelle, Arnau Pino, Andrés, Bergeret Sbarbaro, F. Sebastian, Laboratoire Ondes et Matière d'Aquitaine (LOMA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Université de Bordeaux, Universidad del País Vasco. Facultad de ciencias, Alexandre Bouzdine, F. Sebastián Bergeret, Jérôme Cayssol, Bergeret, F. S., and Buzdin, Alexander I.
Subjects: Inhomogeneous superconducting phase, Phase supraconductrice inhomogène, superconductividad, Superconductivity, Yu-Shiba-Rusinov states, Courant anomal, Champs dépendant du spin, Néel Skyrmion, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], propiedades magnéticas de los sólidos, Condensed Matter::Superconductivity, Anomalous current, Skyrmion de Néel, Etats de Yu-Shiba-Rusinov, Spin-Dependent fields, Supraconductivité
Abstract: [EN]: The interplay between superconductivity and spin-dependent fields is known to lead to striking phenomena, like critical field enhancement, magnetoelectric effects and the appearance of Yu-Shiba-Rusinov bound states at magnetic impurities. In this thesis, we investigate these effects in low dimensional systems.We first demonstrate that the combination of both spin-orbit and Zeeman fields in superconducting one-dimensional systems leads to the appearance of an inhomogeneous phase at low magnetic field and high critical temperature. We show that the ground state corresponds to a zero-current state where the current stemming from spin-orbit coupling, called anomalous charge current, is exactly compensated by the current coming from the wave-vector of the superconducting order parameter. We also discuss how it is possible to predict the appearance of the anomalous current from symmetry arguments based on the SU(2)-covariant formalism.In a second part, we consider a type-II superconducting thin film in contact with a Néel skyrmion. The skyrmion induces spontaneous currents in the superconducting layer, which under the right condition generate a superconducting vortex in the absence of external magnetic fields. We compute the magnetic field and current distributions in the superconducting layer in the presence of the Néel skyrmion.In the last part of this thesis, we focus on the appearance of Yu-Shiba-Rusinov states in the superconducting crystal ß-Bi2Pd. We propose effective models in order to explain recent experimental results showing a double spatial oscillation of the local density of states at Shiba energy. We demonstrate that the minimal condition to reproduce this double oscillation is the presence of two superconducting channels connected via a hopping term or via a magnetic impurity. These effective models can be easily generalized to describe the spectrum of multiband superconductors with magnetic impurities. [FR]: Lorsqu’un supraconducteur est soumis à des champs dépendant du spin, on observe l’émergence de nouveaux phénomènes comme l’augmentation du champ magnétique critique, des effets magnétoélectriques ou encore l’apparition d’états de bord de Yu-Shiba-Rusinov autour d’impuretés magnétiques. Dans cette thèse, on s’intéresse à ces effets dans des systèmes de basse dimension. Tout d’abord, on démontre que la combinaison d’un champ Zeeman avec un couplage spin-orbite dans des systèmes supraconducteurs unidimensionnels induit une phase inhomogène à faible champ magnétique et haute température critiques. On montre que l’état fondamental correspond à un état de courant nul, où le courant induit par le couplage spin-orbite, nommé courant de charges anomal, est exactement compensé par le courant venant du vecteur d’onde du paramètre d’ordre supraconducteur. On discute également la possibilité de prédire l’apparition du courant anomal à partir d’arguments de symétrie basés sur le formalisme covariant SU(2). Dans un second temps, on considère une couche mince supraconductrice de type II en contact avec un skyrmion de Néel. Ce dernier induit des courants spontanés dans la couche supraconductrice, pouvant conduire à l’émergence d’un vortex supraconducteur en l’absence de champ magnétique extérieur. Les distributions de champ magnétique et de courant sont calculées dans le supraconducteur en présence du skyrmion de Néel. La dernière partie de cette thèse est consacrée à l’étude de l’apparition d’états de Yu-Shiba-Rusinov dans le cristal β-Bi2Pd. On propose des modèles effectifs pour expliquer les récents résultats expérimentaux montrant une double oscillation spatiale de la densité d’états locale à l’énergie de Shiba. On démontre que la condition minimale pour reproduire cette double oscillation correspond à la présence de deux canaux supraconducteurs connectés via un terme de saut ou via une impureté magnétique. Ces modèles effectifs peuvent facilement être généralisés pour décrire le spectre de supraconducteurs multi-bandes en présence d’impuretés magnétiques.
Published: 2019

30. Single-Photon Emission Mediated by Single-Electron Tunneling in Plasmonic Nanojunctions

Author: SCHAEVERBEKE, Q., AVRILLER, Rémi, FREDERIKSEN, T., PISTOLESI, F., Laboratoire Ondes et Matière d'Aquitaine (LOMA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Laboratoire de physique et modélisation des milieux condensés (LPM2C), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Condensed Matter - Mesoscale and Nanoscale Physics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), FOS: Physical sciences, ComputingMilieux_MISCELLANEOUS, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]
Abstract: International audience; −3 −2 −1 0 1 2 3 eV L /ωc −1.0 −0.5 0.0 0.5 1.0 −I/eΓ λ = 0.1 λ = 0.3 λ = 0.6 λ = 0.8 λ = 1.4 λ = 2.0 λ = 0.8 λ = 1.4 λ = 2.0; Recent scanning tunneling microscopy (STM) experiments reported single-molecule fluorescence induced by tunneling currents in the nanoplasmonic cavity formed by the STM tip and the substrate. The electric field of the cavity mode couples with the current-induced charge fluctuations of the molecule, allowing the excitation of photons. We investigate theoretically this system for the experimentally relevant limit of large damping rate κ for the cavity mode and arbitrary coupling strength to a single-electronic level. We find that for bias voltages close to the first inelastic threshold of photon emission, the emitted light displays antibunching behavior with vanishing second-order photon correlation function. At the same time, the current and the intensity of emitted light display Franck-Condon steps at multiples of the cavity frequency ω c with a width controlled by κ rather than the temperature T. For large bias voltages, we predict strong photon bunching of the order of κ=Γ where Γ is the electronic tunneling rate. Our theory thus predicts that strong coupling to a single level allows current-driven nonclassical light emission. Electronic transport coupled to the field of an electromagnetic cavity can be realized in a wealth of different systems. This includes in the microwave range carbon nanotubes [1-5], quantum dots [6-9], and Josephson junctions [10-12], or in the optical range, molecules in plasmonic nanocavities formed by an STM tip with a substrate [13-24] and organic microcavities [25-27], or with waveguide quantum electrodynamic systems [28-30]. The reduction of the cavity volume V results in an increase of the zero-point quantum fluctuations of the electric field E zpm ∼ V −1=2. This motivated optical studies of molecular two-level systems strongly coupled to the cavity field by the dipolar interaction Λ d ∼ pE zpm , (with p the molecule dipole moment). One of the goals of this effort is to reach Λ d larger than κ, which has been and remains challenging, despite recent achievements [31]. On the other side, the coupling of a cavity mode to the current-induced charge fluctuations of a single-electronic level is given by a monopolar coupling constant Λ m ∼ eLE zpm as derived in Ref. [32] (see also Ref. [33]), with L the typical extension of the transport region and e the electronic charge. Since typically in a given system eL ≫ p, the monopolar coupling constant is much larger than the dipolar one [32]. This probably contributed to the observation of values of Λ m larger than κ in microwave cavities coupled to electronic transport [4,6,8] and even approaching the cavity resonating frequency ω c (ℏ ¼ 1) [11,39,40]. Recent results in plas-monic cavities coupled to electronic transport [17,21,22] thus open the possibility to explore transport through a single electronic level in these structures. This is expected to reach much larger coupling constants than those currently observed for purely dipolar coupling, requiring further theoretical investigations. The system presents strong analogies with electron transport coupled to molecular vibrations. This has been investigated in different regimes, leading to the striking prediction of the Franck-Condon blockade [34,41,42] and its observation [35,43]. However, there are important differences. The first is the low quality factor of plasmonic cavities, which is typically of the order of 10 [31]. The second, and more interesting, is that the state of the optical or microwave cavity can be directly measured by detecting the emitted photons. It is thus important to investigate how transport through a molecule is linked to the property of the emitted radiation [44-46]. In this Letter we consider electronic transport through a single-level quantum dot, where the charge on the dot is coupled to the electric field of an electromagnetic cavity. We propose a theoretical model to obtain the current through the quantum dot taking into account the cavity dissipation κ, and arbitrary values of the coupling strength in the incoherent transport regime Γ ≪ k B T, with Γ the electron tunneling rate, T the temperature, and k B the
Published: 2019
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31. The methylome of the celiac intestinal epithelium harbours genotype-independent alterations in the HLA region

Author: Nora Fernandez-Jimenez, Leticia Plaza-Izurieta, Vincent Cahais, Iñaki Irastorza, Irati Romero-Garmendia, Maria Legarda, D Degli Esposti, Zdenko Herceg, Koldo Garcia-Etxebarria, Jose Ramon Bilbao, Szilvia Ecsedi, Amaia Jauregi-Miguel, Cyrille Cuenin, Ainara Castellanos-Rubio, Hector Hernandez-Vargas, Epigenetics Group, International Agency for Research on Cancer (IARC), Department of Genetics, Physical Anthropology and Animal Physiology, Biocruces-Bizkaia Health Research Institute, University of the Basque Country [Bizkaia] (UPV/EHU)-University of the Basque Country [Bizkaia] (UPV/EHU)-Biocruces-Bizkaia Health Research Institute, University of the Basque Country [Bizkaia] (UPV/EHU)-University of the Basque Country [Bizkaia] (UPV/EHU), Department of Gastrointestinal and Liver Diseases, Biodonostia Health Research Institute, Pediatric Gastroenterology Unit, Hospital Universitario Cruces = Cruces University Hospital, Institut de Biologie Valrose (IBV), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Spanish Biomedical Research Center in Diabetes and associated Metabolic Disorders (CIBERDEM), Milieux aquatiques, écologie et pollutions (UR MALY), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Department of Immunology, Virology and Inflammation, TGF beta and Immune Evasion Group, Cancer Research Center of Lyon, Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Cancer Research Center of Lyon, Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Leon Berard Hospital, ISCIII Research Project PI13/01201PI16/00258European Union ERDF/ESF - Spanish Ministry of Economy and Competitiveness European Union (EU) Basque Government2011/111034IARC Basque Department of Education University of Basque Country IARC Postdoctoral Fellowship program, Cruces University Hospital, COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-Biocruces-Bizkaia Health Research Institute, University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), and Lallemant, Christopher
Subjects: Male, 0301 basic medicine, lymphocytes, Biopsy, epigenome, dna methylation, Expression, Associations, Epigenome, [SPI]Engineering Sciences [physics], 0302 clinical medicine, HLA Antigens, Mechanisms, Lymphocytes, Intestinal Mucosa, Promoter Regions, Genetic, Cancer, Genetics, mechanisms, Multidisciplinary, Methylation, Wide Analysis, 3. Good health, SNP genotyping, wide analysis, CpG site, DNA methylation, Medicine, Female, associations, Genotype, [SPI] Engineering Sciences [physics], Science, Single-nucleotide polymorphism, Locus (genetics), Human leukocyte antigen, Quantitative trait locus, Biology, Dna Methylation, Article, 03 medical and health sciences, bioconductor package, Bioconductor Package, expression, Inflammatory-bowel-disease, Humans, cancer, inflammatory-bowel-disease, Gene Expression Profiling, Celiac Disease, 030104 developmental biology, Gene Expression Regulation, CpG Islands, 030217 neurology & neurosurgery, Genome-Wide Association Study
Abstract: The Human Leucocyte Antigen (HLA) locus and other DNA sequence variants identified in Genome-Wide Association (GWA) studies explain around 50% of the heritability of celiac disease (CD). However, the pathogenesis of CD could be driven by other layers of genomic information independent from sequence variation, such as DNA methylation, and it is possible that allele-specific methylation explains part of the SNP associations. Since the DNA methylation landscape is expected to be different among cell types, we analyzed the methylome of the epithelial and immune cell populations of duodenal biopsies in CD patients and controls separately. We found a cell type-specific methylation signature that includes genes mapping to the HLA region, namely TAP1 and HLA-B. We also performed Immunochip SNP genotyping of the same samples and interrogated the expression of some of the affected genes. Our analysis revealed that the epithelial methylome is characterized by the loss of CpG island (CGI) boundaries, often associated to altered gene expression, and by the increased variability of the methylation across the samples. The overlap between differentially methylated positions (DMPs) and CD-associated SNPs or variants contributing to methylation quantitative trait loci (mQTLs) is minimal. In contrast, there is a notable enrichment of mQTLs among the most significant CD-associated SNPs. Our results support the notion that DNA methylation alterations constitute a genotype-independent event and confirm its role in the HLA region (apart from the well-known, DQ allele-specific effect). Finally, we find that a fraction of the CD-associated variants could exert its phenotypic effect through DNA methylation. The authors thank the technical and human support provided by SGIker of the UPV/EHU and the Genomics Platform at the CIC bioGUNE. We also thank Dr Florence Le Calvez-Kelm and Mr Geoffroy Durand from the Genetic Cancer Susceptibility group (IARC, Lyon) for their help with the HM450 beadchip assays. The work was funded by ISCIII Research Project Grants PI13/01201 and PI16/00258, cofunded by the European Union ERDF/ESF "A way to make Europe" co-financed by the Spanish Ministry of Economy and Competitiveness -http://www.mineco.gob.es/-and by the European Union ERDF/ESF "A way to make Europe" and project 2011/111034 from the Basque Department of Health -http://www.euskadi.eus/gobierno-vasco/departamento-salud/inicio/-to J.R.B. N.F.J. was supported by an IARC Postodctoral Fellowship (FP7 Marie Curie Actions-People-COFUND) and a Postdoctoral Fellowship from the Basque Department of Education -http://training.iarc.fr/en/fellowships/postdoc.php-.I.R.G.and A.J.M. are supported by Predoctoral Fellowship grants from the UPV/EHU and the Basque Department of Education -http://www.euskadi.eus/gobierno-vasco/departamento-educacion/-, respectively. S.E. was supported by the abovementioned IARC Postdoctoral Fellowship program. ACR is an Ikerbasque Research Fellow -http://www.ikerbasque.net/-.The funding bodies had no role in the design of the study and collection, analysis, and interpretation of data nor in writing the manuscript.
Published: 2019
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32. Electronic transport in planar atomic-scale structures measured by two-probe scanning tunneling spectroscopy

Author: Hiroyo Kawai, Marek Szymonski, Rafal Zuzak, Daniel Sánchez-Portal, Thomas Frederiksen, Marek Kolmer, Szymon Godlewski, Nicolás Lorente, Aran Garcia-Lekue, Christian Joachim, Pedro Brandimarte, Jakub Lis, Centre for Nanometer-Scale Science and Advanced Materials (NANOAM), Uniwersytet Jagielloński w Krakowie = Jagiellonian University (UJ), Center for Nanophase Materials Sciences [Oak Ridge] (CNMS), Oak Ridge National Laboratory [Oak Ridge] (ORNL), UT-Battelle, LLC-UT-Battelle, LLC, Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Agency for science, technology and research [Singapore] (A*STAR), Donostia International Physics Center - DIPC (SPAIN), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ikerbasque - Basque Foundation for Science, Sciences Economiques et Sociales de la Santé & Traitement de l'Information Médicale (SESSTIM - U1252 INSERM - Aix Marseille Univ - UMR 259 IRD), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Groupe NanoSciences (CEMES-GNS), Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Center of Materials Physics CSIC-UPV / EHU and Donostia International Physics Center, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), European Commission, Ministry of Science and Higher Education (Poland), Ministerio de Economía y Competitividad (España), Brandimarte, Pedro, Zuzak, Rafał, Godlewski, Szymon, Frederiksen, Thomas, Institut National des Sciences Appliquées (INSA)-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées (INSA)-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), DUJARDIN, Erik, Brandimarte, Pedro [000-0002-8762-5876], Zuzak, Rafał [0000-0001-6617-591X], Godlewski, Szymon [0000-0002-8515-1566], and Frederiksen, Thomas [0000-0001-7523-7641]
Subjects: 0301 basic medicine, Materials science, Science, Transconductance, Scanning tunneling spectroscopy, General Physics and Astronomy, 02 engineering and technology, Electron, Atomic units, Molecular physics, General Biochemistry, Genetics and Molecular Biology, Article, [PHYS] Physics [physics], 03 medical and health sciences, Scanning probe microscopy, Miniaturization, Physics::Atomic and Molecular Clusters, lcsh:Science, Surface states, Condensed Matter::Quantum Gases, [PHYS]Physics [physics], Multidisciplinary, General Chemistry, 021001 nanoscience & nanotechnology, Characterization (materials science), 030104 developmental biology, lcsh:Q, 0210 nano-technology
Abstract: Miniaturization of electronic circuits into the single-atom level requires novel approaches to characterize transport properties. Due to its unrivaled precision, scanning probe microscopy is regarded as the method of choice for local characterization of atoms and single molecules supported on surfaces. Here we investigate electronic transport along the anisotropic germanium (001) surface with the use of two-probe scanning tunneling spectroscopy and first-principles transport calculations. We introduce a method for the determination of the transconductance in our two-probe experimental setup and demonstrate how it captures energy-resolved information about electronic transport through the unoccupied surface states. The sequential opening of two transport channels within the quasi-one-dimensional Ge dimer rows in the surface gives rise to two distinct resonances in the transconductance spectroscopic signal, consistent with phase-coherence lengths of up to 50 nm and anisotropic electron propagation. Our work paves the way for the electronic transport characterization of quantum circuits engineered on surfaces., This work was supported by the FP7 FET-ICT “Planar Atomic and Molecular Scale devices” (PAMS) project (funded by the European Commission under contract number 610446), the Polish Ministry for Science and Higher Education from financial resources for science in 2013–2017 granted for an international co-financed project (contract number 2913/7.PR/2013/2) and the Spanish Ministerio de Economía y Competitividad (MINECO) (Grant Numbers MAT2016-78293-C6-4-R and FIS2017-83780-P). M.K. acknowledges financial support received from the Polish Ministry of Science and Higher Education, contract number 0341/IP3/2016/74.
Published: 2019
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33. Strong anharmonicity and high thermoelectric efficiency in high temperature SnS from first-principles

Author: Matteo Calandra, Ion Errea, Lorenzo Monacelli, Raffaello Bianco, Francesco Mauri, Aitor Bergara, Unai Aseginolaza, Lorenzo Paulatto, Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Donostia International Physics Center (DIPC), Donostia International Physics Center - DIPC (SPAIN), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Ministerio de Economía y Competitividad (España), and Eusko Jaurlaritza
Subjects: [PHYS]Physics [physics], Condensed Matter - Materials Science, Materials science, Thermoelectric efficiency, Condensed matter physics, Anharmonicity, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, 02 engineering and technology, Power factor, 021001 nanoscience & nanotechnology, Thermoelectric materials, 01 natural sciences, 7. Clean energy, Measure (mathematics), Phase (matter), 0103 physical sciences, Figure of merit, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology, Phase diagram
Abstract: SnS and SnSe are isoelectronic materials with a common phase diagram. Recently, SnSe was found to be the most efficient intrinsic thermoelectric material in its high-temperature Cmcm phase above 800 K. Making use of first-principles calculations, here we show that the electronic and vibrational properties of both materials are very similar in this phase and, consequently, SnS is also expected to have a high thermoelectric figure of merit at high temperature in its Cmcm phase. In fact, the electronic power factor and lattice thermal conductivity are comparable for both materials, which ensures a similar figure of merit. As in the case of SnSe, the vibrational properties of SnS in the Cmcm phase are far from trivial and are dominated by huge anharmonic effects. Its phonon spectra are strongly renormalized by anharmonicity and the spectral functions of some particular in-plane modes depict anomalous non-lorentzian profiles. Finally, we show that non-perturbative anharmonic effects in the third-order force-constants are crucial in the calculation of the lattice thermal conductivity. Our results motivate new experiments in the high temperature regime to measure the figure of merit of SnS., Financial support was provided by the Spanish Ministry of Economy and Competitiveness (FIS2016-76617-P); and the Department of Education, Universities and Research of the Basque Government and the University of the Basque Country (IT756-13). U.A. is alsovthankful to the Material Physics Center for a predoctoral fellowship. Computer facilities were provided by the Donostia International Physics Center (DIPC), PRACE (2017174186) and DARI (A0050901202).
Published: 2019

34. Anharmonic melting of the charge density wave in single-layer TiSe2

Author: Zhou, Jianqiang Sky, Monacelli, Lorenzo, Bianco, Raffaello, Errea, Ion, Mauri, Francesco, Calandra, Matteo, Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica [Roma La Sapienza], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), IIT Graphene Labs, Istituto Italiano di Tecnologia (IIT), Spectroscopie des nouveaux états quantiques (INSP-E2), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Calandra, Matteo
Subjects: [PHYS]Physics [physics], Condensed Matter - Materials Science, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], [PHYS.COND] Physics [physics]/Condensed Matter [cond-mat], [PHYS] Physics [physics]
Abstract: Low dimensional systems with a vanishing band-gap and a large electron-hole interaction have been proposed to be unstable towards exciton formation. As the exciton binding energy increases in low dimension, conventional wisdom suggests that excitonic insulators should be more stable in 2D than in 3D. Here we study the effects of the electron-hole interaction and anharmonicity in single-layer TiSe2. We find that, contrary to the bulk case and to the generally accepted picture, the electron-hole exchange interaction is much smaller in 2D than in 3D and it has negligible effects on phonon spectra. By calculating anharmonic phonon spectra within the stochastic self-consistent harmonic approximation, we obtain TCDW = 440K for an isolated and undoped single-layer and TCDW = 364K for an electron-doping n = 4.6 x 10^13 cm^{-2} , close to the experimental result of 200-280K on supported samples. Our work demonstrates that anharmonicity and doping melt the charge density wave in single-layer TiSe2., 5 pages, 4 figures
Published: 2019

35. Multicolor multiscale brain imaging with chromatic multiphoton serial microscopy

Author: Karine Loulier, Ignacio Arganda-Carreras, Xavier Solinas, Stephen G. Turney, Jean Livet, Solène Clavreul, Willy Supatto, Pierre Mahou, Alexis-Pierre Bemelmans, Emmanuel Beaurepaire, Jeff W. Lichtman, Katherine Matho, Anatole Chessel, Lamiae Abdeladim, Jean-Marc Sintes, Laboratoire d'Optique et Biosciences (LOB), École polytechnique (X)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de la Vision, Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Cold Spring Harbor Laboratory (CSHL), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Department of Molecular and Cellular Biology, and Center for Brain Science, Harvard University, Institut de Biologie François JACOB (JACOB), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Harvard University [Cambridge], Arnoux, Aurélien, and Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)
Subjects: 0301 basic medicine, General Physics and Astronomy, 02 engineering and technology, Nestin, Mice, Parvovirinae, generation, Microscopy, Multiphoton excitation, double markers, lcsh:Science, Cerebral Cortex, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Multidisciplinary, Pyramidal Cells, Resolution (electron density), Dependovirus, organization, 021001 nanoscience & nanotechnology, Fluorescence, Neuroanatomical Tract-Tracing Techniques, [SDV.MHEP.OS] Life Sciences [q-bio]/Human health and pathology/Sensory Organs, Models, Animal, Female, 0210 nano-technology, [PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], Materials science, ex-vivo, Channel (digital image), fluorescent proteins, Science, Genetic Vectors, Color, Mice, Transgenic, Neuroimaging, Transfection, General Biochemistry, Genetics and Molecular Biology, 03 medical and health sciences, Imaging, Three-Dimensional, Optics, Animals, Humans, Image acquisition, Chromatic scale, [SDV.MHEP.OS]Life Sciences [q-bio]/Human health and pathology/Sensory Organs, gene, axonal projections, business.industry, General Chemistry, cell, mosaic analysis, Mice, Inbred C57BL, Luminescent Proteins, HEK293 Cells, Microscopy, Fluorescence, Multiphoton, 030104 developmental biology, mouse-brain, Astrocytes, lcsh:Q, business
Abstract: Large-scale microscopy approaches are transforming brain imaging, but currently lack efficient multicolor contrast modalities. We introduce chromatic multiphoton serial (ChroMS) microscopy, a method integrating one-shot multicolor multiphoton excitation through wavelength mixing and serial block-face image acquisition. This approach provides organ-scale micrometric imaging of spectrally distinct fluorescent proteins and label-free nonlinear signals with constant micrometer-scale resolution and sub-micron channel registration over the entire imaged volume. We demonstrate tridimensional (3D) multicolor imaging over several cubic millimeters as well as brain-wide serial 2D multichannel imaging. We illustrate the strengths of this method through color-based 3D analysis of astrocyte morphology and contacts in the mouse cerebral cortex, tracing of individual pyramidal neurons within densely Brainbow-labeled tissue, and multiplexed whole-brain mapping of axonal projections labeled with spectrally distinct tracers. ChroMS will be an asset for multiscale and system-level studies in neuroscience and beyond. We thank Minh-Son Phan, Samuel Tozer, and Z. Josh Huang for scientific discussions and comments on the manuscript. We thank TissueVision for providing technical advice for the implementation and customization of the block-face system. We thank Bastien Binet from Polytechnique Polymedia center for his generous help in the creation of 3D graphics. We thank IdV core imaging, animal experimentation and histology facilities for technical assistance. This work was supported by fellowships from Universite Paris-Saclay (Initiatives Doctorales Interdisciplinaires) to L.A., Ecole des Neurosciences de Paris to K.M., Region Ile-de-France and Fondation ARC pour la Recherche sur le Cancer to S.C. by Agence Nationale de la Recherche under contracts ANR-11-EQPX-0029 (Equipex Morphoscope2), ANR-10-INBS-04 (France BioImaging), and ANR-10-LABX-65 (LabEx LifeSenses), by Fondation pour la Recherche Medicale (grant DBI20141231328), by Target ALS and by the European Research Council (ERC-CoG 649117).
Published: 2019
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36. Temperature dependence of X-ray absorption and nuclear magnetic resonance spectra: probing quantum vibrations of light elements in oxides

Author: Christel Gervais, Ruidy Nemausat, Nicolas Trcera, Delphine Cabaret, Pierre Florian, Aydar Rakhmatullin, Lorenzo Paulatto, Michele Lazzeri, Amélie Bordage, Ion Errea, Cristina Coelho-Diogo, Christian Brouder, Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Spectroscopie, Modélisation, Interfaces pour L'Environnement et la Santé (LCMCP-SMiLES), Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des matériaux de Paris-Centre (IMPC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Labex Matisse, ANR-11-IDEX-0004,SUPER,Sorbonne Universités à Paris pour l'Enseignement et la Recherche(2011), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Berlinite, General Physics and Astronomy, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Thermal expansion, Spectral line, XANES, 0104 chemical sciences, Condensed Matter::Materials Science, Nuclear magnetic resonance, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, 0210 nano-technology, Quantum statistical mechanics, Absorption (electromagnetic radiation), Quantum fluctuation, Stishovite
Abstract: International audience; A combined experimental-theoretical study on the temperature dependence of x-ray absorption near-edge structure (XANES) and nuclear magnetic resonance (NMR) spectra of periclase (MgO), spinel (MgAl 2 O 4), corundum (α-Al 2 O 3), berlinite (α-AlPO 4), stishovite and α-quartz (SiO 2) is reported. Predictive calculations are presented when experimental data are not available. For these light-element oxides, both experimental techniques detect systematic effects related to quantum thermal vibrations which are well reproduced by density-functional theory simulations. In calculations, thermal fluctuation of the nuclei are included by considering nonequilib-rium configurations according to finite-temperature quantum statistics at the quasiharmonic level. Nuclear quantum fluctuations on XANES and NMR spectroscopies are particularly sensitive to the coordination number of the probed cation. Furthermore, the relative importance of nuclear dynamics and thermal expansion is quantified over a large range of temperatures.
Published: 2017
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37. Transport and spectral properties of low-dimensional superconductors in the presence of spin-dependent fields

Author: BAUMARD, Julie, Bergeret, F. S., Buzdin, Alexander I., Laboratoire Ondes et Matière d'Aquitaine (LOMA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Centro de Fisica de Materiales (CFM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Université de Bordeaux, Universidad del País Vasco. Facultad de ciencias, Alexandre Bouzdine, F. Sebastián Bergeret, Jérôme Cayssol, Philippe Tamarat [Président], Manuel Houzet [Rapporteur], Pascal Simon [Rapporteur], Andrès Arnau Pino, and Hélène Bouchiat
Subjects: Inhomogeneous superconducting phase, Phase supraconductrice inhomogène, Superconductivity, Yu-Shiba-Rusinov states, Courant anomal, Champs dépendant du spin, Néel Skyrmion, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Condensed Matter::Superconductivity, Anomalous current, Skyrmion de Néel, Etats de Yu-Shiba-Rusinov, Spin-Dependent fields, Supraconductivité
Abstract: [EN]: The interplay between superconductivity and spin-dependent fields is known to lead to striking phenomena, like critical field enhancement, magnetoelectric effects and the appearance of Yu-Shiba-Rusinov bound states at magnetic impurities. In this thesis, we investigate these effects in low dimensional systems.We first demonstrate that the combination of both spin-orbit and Zeeman fields in superconducting one-dimensional systems leads to the appearance of an inhomogeneous phase at low magnetic field and high critical temperature. We show that the ground state corresponds to a zero-current state where the current stemming from spin-orbit coupling, called anomalous charge current, is exactly compensated by the current coming from the wave-vector of the superconducting order parameter. We also discuss how it is possible to predict the appearance of the anomalous current from symmetry arguments based on the SU(2)-covariant formalism.In a second part, we consider a type-II superconducting thin film in contact with a Néel skyrmion. The skyrmion induces spontaneous currents in the superconducting layer, which under the right condition generate a superconducting vortex in the absence of external magnetic fields. We compute the magnetic field and current distributions in the superconducting layer in the presence of the Néel skyrmion.In the last part of this thesis, we focus on the appearance of Yu-Shiba-Rusinov states in the superconducting crystal ß-Bi2Pd. We propose effective models in order to explain recent experimental results showing a double spatial oscillation of the local density of states at Shiba energy. We demonstrate that the minimal condition to reproduce this double oscillation is the presence of two superconducting channels connected via a hopping term or via a magnetic impurity. These effective models can be easily generalized to describe the spectrum of multiband superconductors with magnetic impurities., [FR]: Lorsqu’un supraconducteur est soumis à des champs dépendant du spin, on observe l’émergence de nouveaux phénomènes comme l’augmentation du champ magnétique critique, des effets magnétoélectriques ou encore l’apparition d’états de bord de Yu-Shiba-Rusinov autour d’impuretés magnétiques. Dans cette thèse, on s’intéresse à ces effets dans des systèmes de basse dimension. Tout d’abord, on démontre que la combinaison d’un champ Zeeman avec un couplage spin-orbite dans des systèmes supraconducteurs unidimensionnels induit une phase inhomogène à faible champ magnétique et haute température critiques. On montre que l’état fondamental correspond à un état de courant nul, où le courant induit par le couplage spin-orbite, nommé courant de charges anomal, est exactement compensé par le courant venant du vecteur d’onde du paramètre d’ordre supraconducteur. On discute également la possibilité de prédire l’apparition du courant anomal à partir d’arguments de symétrie basés sur le formalisme covariant SU(2). Dans un second temps, on considère une couche mince supraconductrice de type II en contact avec un skyrmion de Néel. Ce dernier induit des courants spontanés dans la couche supraconductrice, pouvant conduire à l’émergence d’un vortex supraconducteur en l’absence de champ magnétique extérieur. Les distributions de champ magnétique et de courant sont calculées dans le supraconducteur en présence du skyrmion de Néel. La dernière partie de cette thèse est consacrée à l’étude de l’apparition d’états de Yu-Shiba-Rusinov dans le cristal β-Bi2Pd. On propose des modèles effectifs pour expliquer les récents résultats expérimentaux montrant une double oscillation spatiale de la densité d’états locale à l’énergie de Shiba. On démontre que la condition minimale pour reproduire cette double oscillation correspond à la présence de deux canaux supraconducteurs connectés via un terme de saut ou via une impureté magnétique. Ces modèles effectifs peuvent facilement être généralisés pour décrire le spectre de supraconducteurs multi-bandes en présence d’impuretés magnétiques.
Published: 2019

38. Composite boson signature in the interference pattern of atomic dimer condensates

Author: Aurélia Chenu, Monique Combescot, Shiue-Yuan Shiau, National Center for Theoretical Sciences [Taiwan] (NCTS), National Taiwan University [Taiwan] (NTU), Los Alamos National Laboratory (LANL), Massachusetts Institute of Technology (MIT), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Photons, Magnons et Technologies Quantiques (INSP-E11), and Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Spatial correlation, Dimer, optical lattice, Physics [G04] [Physical, chemical, mathematical & earth Sciences], General Physics and Astronomy, FOS: Physical sciences, 01 natural sciences, Molecular physics, 010305 fluids & plasmas, chemistry.chemical_compound, symbols.namesake, Pauli exclusion principle, BEC, Lattice (order), 0103 physical sciences, 010306 general physics, Boson, Physics, Condensed Matter::Quantum Gases, [PHYS]Physics [physics], Optical lattice, Quantum Physics, composite boson, Fermion, Physique [G04] [Physique, chimie, mathématiques & sciences de la terre], chemistry, Quantum Gases (cond-mat.quant-gas), symbols, interference pattern, atomic dimer, Granularity, Condensed Matter - Quantum Gases, Quantum Physics (quant-ph)
Abstract: We predict the existence of high frequency modes in the interference pattern of two condensates made of fermionic-atom dimers. These modes, which result from fermion exchanges between condensates, constitute a striking signature of the dimer composite nature. From the 2-coboson spatial correlation function, that we derive analytically, and the Shiva diagrams that visualize many-body effects specific to composite bosons, we identify the physical origin of these high frequency modes and determine the conditions to see them experimentally by using bound fermionic-atom pairs trapped on optical lattice sites. The dimer granularity which appears in these modes comes from Pauli blocking that prevents two dimers to be located at the same lattice site., Comment: 10+7 pp, 3 figures. v2: version accepted for publication in New J. Phys
Published: 2019
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39. Quantum effects in muon spin spectroscopy within the stochastic self-consistent harmonic approximation

Author: Pietro Bonfà, Francesco Mauri, Ifeanyi John Onuorah, Lorenzo Monacelli, Matteo Calandra, Ion Errea, Roberto De Renzi, European Commission, Swiss National Supercomputing Centre, Science and Technology Facilities Council (UK), Università degli Studi di Parma, Ministerio de Economía y Competitividad (España), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), and University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)
Subjects: [PHYS]Physics [physics], Condensed Matter - Materials Science, Materials science, Physics and Astronomy (miscellaneous), Library science, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, 02 engineering and technology, Self consistent, 021001 nanoscience & nanotechnology, 01 natural sciences, 0103 physical sciences, media_common.cataloged_instance, General Materials Science, Christian ministry, European union, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Physics::Chemical Physics, 010306 general physics, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, media_common
Abstract: Muon spin rotation experiments involve muons that experience zero-point vibration at their implantation sites. Quantum-mechanical calculations of the host material usually treat the muon as a point impurity, ignoring its zero-point vibrational energy that, however, plays a role in determining the stability of calculated implantation sites and estimating physical observables. As a first-order correction, the muon zero-point motion is usually described within the harmonic approximation, despite the anharmonicity of the crystal potential. Here we apply the stochastic self-consistent harmonic approximation, a quantum variational method devised to include anharmonic effects in total energy and vibrational frequency calculations, in order to overcome these limitations and provide an accurate ab initio description of the quantum nature of the muon. We applied this full quantum treatment to the calculation of the muon contact hyperfine field in textbook-case metallic systems, such as Fe, Ni, Co including MnSi and MnGe, improving agreement with experiments. Our results show that there are anharmonic contributions to the muon vibrational frequencies with the muon zero-point energies above 0.5 eV. Finally, in contrast to the harmonic approximation, we show that including quantum anharmonic fluctuations, the muon stabilizes at the octahedral site in bcc Fe., RDR acknowledges grants from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 654000. RDR, PB and IJO also acknowledge computing resources provided by, the Swiss National Supercomputing Centre (CSCS) under Project ID sm16, CINECA under Project ID IsC58, the STFC Scientific Computing Departments SCARF cluster and the HPC resources at the University of Parma, Italy. IE acknowledges funding from the Spanish Ministry of Economy and Competitiveness (FIS2016-76617-P). This work is part of the PhD thesis of IJO at the University of Parma, Italy
Published: 2019
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40. Doping as a Way To Protect Silicate Chains in Calcium Silicate Hydrates

Author: Andrés Ayuela, Romain Dupuis, Jorge S. Dolado, Jose Surga, Surfaces, Interfaces et Nano-Objets (CEMES-SINanO), Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UPS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Tecnalia [Derio], Intevep, Donostia International Physics Center - DIPC (SPAIN), Eusko Jaurlaritza, Ministerio de Economía y Competitividad (España), Universidad del País Vasco, Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), and University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)
Subjects: Materials science, General Chemical Engineering, Green cement, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, Doping, Environmental Chemistry, [CHIM]Chemical Sciences, Calcium silicate hydrate, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], ComputingMilieux_MISCELLANEOUS, Cement, Bond-breaking, Dopant, Renewable Energy, Sustainability and the Environment, Depolymerization, technology, industry, and agriculture, General Chemistry, 021001 nanoscience & nanotechnology, Silicate chains, Silicate, 0104 chemical sciences, chemistry, Chemical engineering, Calcium silicate, Carbon footprint, 0210 nano-technology
Abstract: A critical challenge in reducing anthropogenic impacts on the environment is to decrease the carbon footprint of the cement industry. A key concern in the search for more sustainable cement designs is the understanding and control of the depolymerization process that eventually determines the integrity of their silicate chains under mechanical, chemical, or thermal stresses. Herein, we use metadynamics to show that the depolymerization of cement silicate skeletons consists of hydroxylation followed by bond-breaking. We then clarify the local effects of doping the silicate chains: a stable pentacoordinate state following hydroxylation is promoted by aluminum atoms but restrained by phosphorus additions, the presence of two dopants being related to energy landscapes less favorable to bond-breaking. The role of these dopants is explained in cement-based materials and is key to the quest for low-cost opportunities to preserve the strength of cement for high temperatures or even over time., This work was supported by the Spanish Government (FIS2016-76617-P), the Basque Government through the ELKARTEK project (SUPER), and the University of the Basque Country (Grant No. IT-756-13).
Published: 2018
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41. High-pressure phase diagram of hydrogen and deuterium sulfides from first principles: structural and vibrational properties including quantum and anharmonic effects

Author: Matteo Calandra, Francesco Mauri, Ion Errea, Raffaello Bianco, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome]
Subjects: Phonon, Anharmonic lattice dynamics, Crystal structure, Phase transitions, Pressure effects, High-temperature superconductors, Density functional theory, superconductivity, first princliples calculations, FOS: Physical sciences, Pressure effects, 02 engineering and technology, 01 natural sciences, 0103 physical sciences, Kinetic isotope effect, Anharmonic lattice dynamics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, Anisotropy, ComputingMilieux_MISCELLANEOUS, Phase diagram, [PHYS]Physics [physics], Physics, Superconductivity, Condensed Matter - Materials Science, Condensed matter physics, Crystal structure, Anharmonicity, Center (category theory), Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Phase transitions, Quasiparticle, 0210 nano-technology
Abstract: We study the structural and vibrational properties of the high-temperature superconducting sulfur trihydride and trideuteride in the high-pressure $Im\overline{3}m$ and $R3m$ phases by first-principles density-functional-theory calculations. On lowering pressure, the rhombohedral transition $Im\overline{3}m\ensuremath{\rightarrow}R3m$ is expected, with hydrogen-bond desymmetrization and occurrence of trigonal lattice distortion. With both Perdew-Burke-Ernzerhof (PBE) and Becke-Lee-Yang-Parr (BLYP) exchange-correlation functional, in hydrostatic conditions we find that, contrary to what is suggested in some recent experiments, if the rhombohedral distortion exists it affects mainly the hydrogen bonds, whereas the resulting cell distortion is minimal. We estimate that the occurrence of a stress anisotropy of approximately $10%$ could explain this discrepancy. Assuming hydrostatic conditions, we calculate the critical pressure at which the rhombohedral transition occurs. Quantum and anharmonic effects, which are relevant in this system, are included at nonperturbative level with the stochastic self-consistent harmonic approximation. Within this approach, we determine the transition pressure by calculating the free-energy Hessian, a method that allows to estimate the critical pressure with much higher precision (and much lower computational cost) compared with the free-energy ``finite-difference'' approach previously used. Using PBE and BLYP, we find that quantum anharmonic effects are responsible for a strong reduction of the critical pressure with respect to the one obtained with the classical harmonic approach. Interestingly, for the two functionals, even if the transition pressures at classical harmonic level differ by 83 GPa, the transition pressures including quantum anharmonic effects differ only by 23 GPa. Moreover, we observe a prominent isotope effect, as we estimate higher transition pressure for ${\mathrm{D}}_{3}\mathrm{S}$ than for ${\mathrm{H}}_{3}\mathrm{S}$. Finally, within the stochastic self-consistent harmonic approximation, with PBE we calculate the anharmonic phonon spectral functions in the $Im\overline{3}m$ phase. The strong anharmonicity of the system is confirmed by the occurrence of very large anharmonic broadenings leading to complex non-Lorentzian line shapes. Generally, for the high-energy hydrogen bond-stretching modes, the anharmonic phonon broadening is of the same magnitude of the electron-phonon one. However, for the vibrational spectra at zone center, accessible, e.g., by infrared spectroscopy, the broadenings are very small (linewidth at most around 2 meV) and anharmonic phonon quasiparticles are well defined.
Published: 2018
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42. Pressure and stress tensor of complex anharmonic crystals within the stochastic self-consistent harmonic approximation

Author: Ion Errea, Francesco Mauri, Lorenzo Monacelli, Matteo Calandra, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome]
Subjects: Thermal properties, Phonon, Computation, FOS: Physical sciences, Thermal fluctuations, Pressure effects, 02 engineering and technology, Stress, 01 natural sciences, Acoustic phonons, Anharmonic lattice dynamics, Crystal structure, Lattice dynamics, Optical phonons, Phonons, Pressure effects, Stress, Structural properties, Thermal expansion, Thermal properties, Lattice (order), 0103 physical sciences, Statistical physics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Anharmonic lattice dynamics, 010306 general physics, phonon, Quantum, ComputingMilieux_MISCELLANEOUS, Condensed Matter - Statistical Mechanics, first principles calculations, [PHYS]Physics [physics], Physics, Condensed Matter - Materials Science, Statistical Mechanics (cond-mat.stat-mech), Structural properties, Cauchy stress tensor, Crystal structure, anharmonicity, Lattice dynamics, Anharmonicity, Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph), 021001 nanoscience & nanotechnology, Homogeneous space, Phonons, Optical phonons, Acoustic phonons, Thermal expansion, 0210 nano-technology, Physics - Computational Physics
Abstract: The self-consisted harmonic approximation (SCHA) allows the computation of free energy of anharmonic crystals considering both quantum and thermal fluctuations. Recently, a stochastic implementation of the SCHA has been developed, tailored for applications that use total energy and forces computed from first principles. In this work, we extend the applicability of the stochastic SCHA to complex crystals with many degrees of freedom, with the optimisation of both the lattice vectors and the atomic positions. To this goal, we provide an expression for the evaluation of the pressure and stress tensor within the stochastic SCHA formalism. Moreover, we develop a more robust free energy minimisation algorithm, which allows us to perform the SCHA variational minimisation very efficiently in systems having a broad spectrum of phonon frequencies and many degrees of freedom. We test and illustrate the new approach with an application to the phase XI of water ice using density-functional theory. We find that the SCHA reproduces extremely well the experimental thermal expansion of ice in the whole temperature range between 0 K and 270 K, in contrast with the results obtained within the quasi-harmonic approximation, that underestimates the effect by about 25 %., 20 pages, 8 figures
Published: 2018
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43. Strong anharmonicity in the phonon spectra of PbTe and SnTe from first principles

Author: Ion Errea, Guilherme A. S. Ribeiro, Matteo Calandra, Lorenzo Paulatto, Raffaello Bianco, Francesco Mauri, Fundação Oswaldo Cruz (FIOCRUZ), Réseau International des Instituts Pasteur (RIIP), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Phonon, 02 engineering and technology, 01 natural sciences, Thermal expansion, Inelastic neutron scattering, Thermoelectric effects, Ferro electricity, Condensed Matter::Materials Science, symbols.namesake, 0103 physical sciences, Elastic-constants, lead-telluride, temperature, dynamics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], Condensed matter physics, Transition temperature, Anharmonicity, Lattice dynamics, 021001 nanoscience & nanotechnology, Thermoelectric materials, Insulators, Ferroelectricity, Semiconductors, Ferro electricity, Insulators, Lattice dynamics, Semiconductors, Thermal expansion, Thermoelectric effects, symbols, 0210 nano-technology, Hamiltonian (quantum mechanics)
Abstract: At room temperature, PbTe and SnTe are efficient thermoelectrics with a cubic structure. At low temperature, SnTe undergoes a ferroelectric transition with a critical temperature strongly dependent on the hole concentration, while PbTe is an incipient ferroelectric. By using the stochastic self-consistent harmonic approximation, we investigate the anharmonic phonon spectra and the occurrence of a ferroelectric transition in both systems. We find that vibrational spectra strongly depend on the approximation used for the exchange-correlation kernel in density-functional theory. If gradient corrections and the theoretical volume are employed, then the calculation of the phonon frequencies as obtained from the diagonalization of the free-energy Hessian leads to phonon spectra in good agreement with experimental data for both systems. In PbTe we evaluate the linear thermal expansion coefficient $\ensuremath{\gamma}=2.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\phantom{\rule{4.pt}{0ex}}{\text{K}}^{\ensuremath{-}1}$, finding it to be in good agreement with experimental value of $\ensuremath{\gamma}=2.04\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\phantom{\rule{4.pt}{0ex}}{\text{K}}^{\ensuremath{-}1}$. Furthermore, we study the phonon spectrum and we do reproduce the transverse optical mode phonon satellite detected in inelastic neutron scattering and the crossing between the transverse optical and the longitudinal acoustic modes along the $\mathrm{\ensuremath{\Gamma}}\mathrm{X}$ direction. The phonon satellite becomes broader at high temperatures but its energy is essentially temperature independent, in agreement with experiments. We decompose the self-consistent harmonic free energy in second-, third-, and fourth-order anharmonic terms. We find that the third- and fourth-order terms are small. However, treating the third-order term perturbatively on top of the second-order self-consistent harmonic free energy overestimates the energy of the satellite associated with the transverse optical mode. On the contrary, a perturbative treatment on top of the harmonic Hamiltonian breaks down and leads to imaginary phonon frequencies already at 300 K. In the case of SnTe, we describe the occurrence of a ferroelectric transition from the high-temperature $Fm\overline{3}m$ structure to the low-temperature $R3m$ one. The transition temperature is, however, underestimated with respect to the experimental one. No satellites are present in the SnTe phonon spectra despite a not negligible anharmonic broadening of the zone-center TO mode.
Published: 2018
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44. Supercritical hydrothermal flow synthesis of xonotlite nanofibers

Author: José I. Santos, Jorge S. Dolado, Juan J. Gaitero, Cyril Aymonier, Marta Diez-Garcia, Eusko Jaurlaritza, Euskampus Fundazioa, Universidad del País Vasco, Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Tecnalia [Derio], Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), the BASKRETE initiative and supported by the Basque Government under the ELKARTEK Program (project SUPER), and the University of the Basque Country (UPV/EHU) and the University of Bordeaux for her pre-doctoral fellowship, within the framework of the Cross-Border Euroregional Campus of International Excellence IDEX Bordeaux–Euskampus.
Subjects: Fluid Flow and Transfer Processes, Green chemistry, Materials science, Xonotlite, Continuous reactor, Organic Chemistry, Nanochemistry, Infrared spectroscopy, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Supercritical fluid, Hydrothermal circulation, 0104 chemical sciences, Chemical engineering, Chemistry (miscellaneous), Nanofiber, 0210 nano-technology, Flow synthesis, Ultra-fast synthesis, Supercritical water
Abstract: This article reports a satisfactory and innovative method for the synthesis of xonotlite using a flow reactor and supercritical water. This study widens the variety of inorganic nanofibers produced in record breaking times by means of continuous reactors working under supercritical water conditions. In particular, the synthesis time of xonotlite, which takes normally more than 5 h, was reduced to only 20s by carrying out the reaction at 400 °C and 23.5 MPa. Resulting product was studied by several characterization techniques: x-ray diffraction, transmission electron microscopy, 29Si and 1H nuclear magnetic resonance and infrared spectroscopy. Furthermore, obtained product consisted of highly pure and crystalline flat nanofibers of 1–10 μm long with a length to diameter ratio of the order of 100. Also, the typical deviation from the ideal structure observed by nuclear magnetic resonance and the presence of Si-OH were explained in terms of surface defects. This work reinforces the interests of using supercritical conditions for the fast synthesis of crystalline nano-calcium silicates which, due to the number of potential industrial applications and the scalability of the technology, might represent technological breakthrough., This study was carried out under the umbrella of the BASKRETE initiative and supported by the Basque Government under the ELKARTEK Program (project SUPER). In addition, Marta Diez is grateful to the University of the Basque Country (UPV/EHU) and the University of Bordeaux for her pre-doctoral fellowship, within the framework of the Cross-Border Euroregional Campus of International Excellence IDEX Bordeaux–Euskampus.
Published: 2018

45. Second order structural phase transitions, free energy curvature, and temperature-dependent anharmonic phonons in the self-consistent harmonic approximation: theory and stochastic implementation

Author: Francesco Mauri, Ion Errea, Lorenzo Paulatto, Matteo Calandra, Raffaello Bianco, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, [PHYS]Physics [physics], Approximation theory, Condensed Matter - Materials Science, Toy model, Phonon, Anharmonicity, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, 02 engineering and technology, Inelastic scattering, 021001 nanoscience & nanotechnology, Curvature, 01 natural sciences, Vibration, Classical mechanics, Quantum mechanics, 0103 physical sciences, Barium-titanate, crystal, scattering, constants, helium, tise2, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology, Second derivative
Abstract: International audience; The self-consistent harmonic approximation is an effective harmonic theory to calculate the free energy of systems with strongly anharmonic atomic vibrations, and its stochastic implementation has proved to be an efficient method to study, from first-principles, the anharmonic properties of solids. The free energy as a function of average atomic positions (centroids) can be used to study quantum or thermal lattice instability. In particular the centroids are order parameters in second-order structural phase transitions such as, e.g., charge-density-waves or ferroelectric instabilities. According to Landau's theory, the knowledge of the second derivative of the free energy (i.e. the curvature) with respect to the centroids in a high-symmetry configuration allows the identification of the phase-transition and of the instability modes. In this work we derive the exact analytic formula for the second derivative of the free energy in the self-consistent harmonic approximation for a generic atomic configuration. The analytic derivative is expressed in terms of the atomic displacements and forces in a form that can be evaluated by a stochastic technique using importance sampling. Our approach is particularly suitable for applications based on first-principles density-functional-theory calculations, where the forces on atoms can be obtained with a negligible computational effort compared to total energy determination. Finally we propose a dynamical extension of the theory to calculate spectral properties of strongly anharmonic phonons, as probed by inelastic scattering processes. We illustrate our method with a numerical application on a toy model that mimics the ferroelectric transition in rock-salt crystals such as SnTe or GeTe.
Published: 2017
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46. Modelling of optimal training load patterns during the 11 weeks preceding major competition in elite swimmers

Author: David B. Pyne, Philippe Hellard, Marta Avalos, Charlotte Scordia, Iñigo Mujika, Institut de recherche biomédicale et d’épidémiologie du sport (IRMES - EA 7329), Université Paris Descartes - Paris 5 (UPD5)-Institut national du sport, de l'expertise et de la performance (INSEP), Fédération Française de Natation (FFN), Université de Bordeaux (UB), Epidémiologie et Biostatistique [Bordeaux], Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM), Statistics In System biology and Translational Medicine (SISTM), Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Epidémiologie et Biostatistique [Bordeaux], Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Australian Institute of Sport, This research was partially funded by the French Institute of Sport, Expertise and Performance (INSEP) and the French Ministry in charge of sports under grant no 14r21, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)- Bordeaux population health (BPH), Université de Bordeaux (UB)-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Bordeaux (UB)-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut de recherche biomédicale et d’épidémiologie du sport ( IRMES - EA 7329 ), Institut national du sport, de l'expertise et de la performance ( INSEP ) -Université Paris Descartes - Paris 5 ( UPD5 ), Fédération Française de Natation ( FFN ), Université de Bordeaux ( UB ), Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale ( INSERM ), Statistics In System biology and Translational Medicine ( SISTM ), Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National de Recherche en Informatique et en Automatique ( Inria ), and University of the Basque Country/Euskal Herriko Unibertsitatea ( UPV/EHU )
Subjects: Male, Periodicity, Time Factors, Physiology, Health Status, Endocrinology, Diabetes and Metabolism, High-Intensity Interval Training, 0302 clinical medicine, cubic splines, natation, [STAT.ML]Statistics [stat]/Machine Learning [stat.ML], modèles mixtes, Training load, swimming, [STAT.CO]Statistics [stat]/Computation [stat.CO], [ STAT.ML ] Statistics [stat]/Machine Learning [stat.ML], Mathematics, media_common, [STAT.AP]Statistics [stat]/Applications [stat.AP], Nutrition and Dietetics, Age Factors, Swim training, [ SDV.SPEE ] Life Sciences [q-bio]/Santé publique et épidémiologie, General Medicine, Improved performance, periodization, [ STAT.ME ] Statistics [stat]/Methodology [stat.ME], Sprint, Muscle Fatigue, splines cubiques, Female, High-intensity interval training, competition, [STAT.ME]Statistics [stat]/Methodology [stat.ME], Muscle Contraction, Physical Conditioning, Human, Adult, mixed models, Competitive Behavior, Adolescent, Strength training, media_common.quotation_subject, Models, Biological, [ INFO.INFO-LG ] Computer Science [cs]/Machine Learning [cs.LG], Competition (biology), Young Adult, 03 medical and health sciences, Sex Factors, Animal science, [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], Physiology (medical), Humans, Muscle Strength, 14. Life underwater, Muscle, Skeletal, [ STAT.CO ] Statistics [stat]/Computation [stat.CO], Models, Statistical, [ STAT.AP ] Statistics [stat]/Applications [stat.AP], Training (meteorology), Resistance Training, 030229 sport sciences, périodisation, Athletes, Physical Endurance, compétition, [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie, 030217 neurology & neurosurgery
Abstract: International audience; Periodization of swim training in the final training phases prior to competition and its effect on performance have been poorly described. We modeled the relationships between the final 11 weeks of training and competition performance in 138 elite sprint, middle-distance, and long-distance swimmers over 20 competitive seasons. Total training load (TTL), strength training (ST), and low- to medium-intensity and high-intensity training variables were monitored. Training loads were scaled as a percentage of the maximal volume measured at each intensity level. Four training periods (meso-cycles) were defined: the taper (weeks 1 to 2 before competition), short-term (weeks 3 to 5), medium-term (weeks 6 to 8), and long-term (weeks 9 to 11). Mixed-effects models were used to analyze the association between training loads in each training meso-cycle and end-of-season major competition performance. For sprinters, a 10% increase between ∼20% and 70% of the TTL in medium- and long-term meso-cycles was associated with 0.07 s and 0.20 s faster performance in the 50 m and 100 m events, respectively (p < 0.01). For middle-distance swimmers, a higher TTL in short-, medium-, and long-term training yielded faster competition performance (e.g., a 10% increase in TTL was associated with improvements of 0.1-1.0 s in 200 m events and 0.3-1.6 s in 400 m freestyle, p < 0.01). For sprinters, a 60%-70% maximal ST load 6-8 weeks before competition induced the largest positive effects on performance (p < 0.01). An increase in TTL during the medium- and long-term preparation (6-11 weeks to competition) was associated with improved performance. Periodization plans should be adapted to the specialty of swimmers.; En natation, la périodisation des phases d’entraînement précédant les compétitions majeures a été peu décrite. Nous avons modélisé les relations entre les 11 dernières semaines d’entraînement et les performances en compétition chez 138 nageurs élites. La charge d’entraînement totale (TTL), l’entraînement de force (ST), les variables d’entraînement de basse à moyenne et haute intensité ont été quantifiées. Les charges d’entraînement ont été normalisées en pourcentage du volume maximal individuel pour chaque niveau d’intensité. Quatre périodes d’entraînement (méso-cycles) ont été définies, l’affutage (semaines 1 à 2 avant la compétition), à court-terme (semaines 3 à 5), moyen-terme (semaines 6 à 8) et long-terme (semaines 9 à 11). Les modèles à effets mixtes ont été utilisés pour analyser les associations entre les charges d’entraînement dans chaque méso-cycle et la performance de fin de saison. Pour les sprinters, chaque augmentation de TTL de 10 % entre ∼20–70 % dans les méso-cycles à long et moyen-terme a été associée avec des performances plus rapides de 0,07 s et 0,20 s dans les épreuves de 50 m et 100 m (p < 0,01). Pour les nageurs de demi-fond une TTL plus élevée à court, moyen et long terme a induit des performances en compétition plus rapides (chaque augmentation de TTL de 10 % entre ∼20–70 % a été associée à des performances plus rapides de 0,3–1,6 s au 400 m, p < 0,01). Pour les sprinters, une ST entre 60–70 % 6–8 semaines avant la compétition a induit les effets positifs les plus élevés (p < 0,01). TTL 6–11 semaines avant la compétition a amélioré les performances en compétition.
Published: 2017
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47. Anharmonicity and the isotope effect in superconducting lithium at high pressures: a first-principles approach

Author: Aitor Bergara, Ion Errea, Miguel Borinaga, Unai Aseginolaza, Matteo Calandra, Francesco Mauri, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Eusko Jaurlaritza, Universidad del País Vasco, and Ministerio de Economía y Competitividad (España)
Subjects: Physics, Superconductivity, [PHYS]Physics [physics], Condensed matter physics, Dense lithium, metal, transition, quantum, phases, Phonon, Isotopes of lithium, Condensed Matter - Superconductivity, Anharmonicity, chemistry.chemical_element, FOS: Physical sciences, 02 engineering and technology, Soft modes, 021001 nanoscience & nanotechnology, 01 natural sciences, 7. Clean energy, Superconductivity (cond-mat.supr-con), chemistry, Phase (matter), 0103 physical sciences, Kinetic isotope effect, Lithium, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology
Abstract: Recent experiments [A. M. Schaeffer et al., Proc. Natl. Acad. Sci. USA 112, 60 (2015)] have shown that lithium presents an extremely anomalous isotope effect in the 15–25 GPa pressure range. In this article we have calculated the anharmonic phonon dispersion of 7Li and 6Li under pressure, their superconducting transition temperatures, and the associated isotope effect. We have found a huge anharmonic renormalization of a transverse acoustic soft mode along ΓK in the fcc phase, the expected structure at the pressure range of interest. In fact, the anharmonic correction dynamically stabilizes the fcc phase above 25 GPa. However, we have not found any anomalous scaling of the superconducting temperature with the isotopic mass. Additionally, we have also analyzed whether the two lithium isotopes adopting different structures could explain the observed anomalous behavior. According to our enthalpy calculations including zero-point motion and anharmonicity it would not be possible in a stable regime., The authors acknowledge financial support from the Spanish Ministry of Economy and Competitiveness (Grant No. FIS2016-76617-P) and the Department of Education, Universities and Research of the Basque Government and the University of the Basque Country (Grant No. IT756-13). M.B. is also thankful to the Department of Education, Language Policy and Culture of the Basque Government for a predoctoral fellowship (Grant No. PRE-2015-2-0269).
Published: 2017
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48. Efficient Spin-Flip Excitation of a Nickelocene Molecule

Author: Benjamin Verlhac, Marie-Laure Bocquet, Loïc Joly, P. N. Abufager, Fabrice Scheurer, Philippe Ohresser, Marisa N. Faraggi, Laurent Limot, M. Ormaza, Nicolás Lorente, Michelangelo Romeo, N. Bachellier, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), scheurer, fabrice, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional de Rosario [Argentina], CEA- Saclay (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centro de Fisica de Materiales (CFM), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), limot, laurent, and Agence Nationale de la Recherche (France)
Subjects: inelastic electron tunneling spectroscopy, Magnetism, Ciencias Físicas, Bioengineering, 02 engineering and technology, 01 natural sciences, law.invention, [PHYS] Physics [physics], law, 0103 physical sciences, Atom, General Materials Science, 010306 general physics, Tip functionalization, Magnetic anisotropy, tip functionalization, density functional theory, Metallocene, [PHYS]Physics [physics], magnetic anisotropy, Magnetic moment, Inelastic electron tunneling spectroscopy, Chemistry, Magnetic circular dichroism, Mechanical Engineering, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, spin-flip, Density functional theory, X-ray magnetic circular dichroism, Atomic physics, Scanning tunneling microscope, Spin-flip, 0210 nano-technology, Excitation, CIENCIAS NATURALES Y EXACTAS, Física de los Materiales Condensados
Abstract: Inelastic electron tunneling spectroscopy (IETS) within the junction of a scanning tunneling microscope (STM) uses current-driven spin-flip excitations for an all-electrical characterization of the spin state of a single object. Usually decoupling layers between the single object, atom or molecule, and the supporting surface are needed to observe these excitations. Here we study the surface magnetism of a sandwich nickelocene molecule (Nc) adsorbed directly on Cu(100) by means of X-ray magnetic circular dichroism (XMCD) and density functional theory (DFT) calculations and show with IETS that it exhibits an exceptionally efficient spin-flip excitation. The molecule preserves its magnetic moment and magnetic anisotropy not only on Cu(100), but also in different metallic environments including the tip apex. By taking advantage of this robusteness, we are able to functionalize the microscope tip with a Nc, which can be employed as a portable source of inelastic excitations as exemplified by a double spin-flip excitation process., This work has been supported by the Agence Nationale de la Recherche (Grant Nos. ANR-13-BS10–0016, ANR-11-LABX-0058 NIE, ANR-10-LABX-0026 CSC).
Published: 2017
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49. Anharmonic effects in atomic hydrogen: Superconductivity and lattice dynamical stability

Author: Matteo Calandra, Francesco Mauri, Ion Errea, Aitor Bergara, Miguel Borinaga, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Ministerio de Economía y Competitividad (España), Eusko Jaurlaritza, Universidad del País Vasco, Agence Nationale de la Recherche (France), and Donostia International Physics Center
Subjects: METALLIC HYDROGEN, Superconductivity, Phonon, SOLID HYDROGEN, DENSE HYDROGEN, HIGH-PRESSURES, PHASE, GPA, TEMPERATURE, GIGAPASCALS, VIBRATIONS, ELECTRONS, Anharmonic lattice dynamics, Electron-phonon coupling, Superconductivity, Elemental materials, High-temperature superconductors, Density functional theory, Free-electron model, Linear response theory, Perturbation theory, Random phase approximation, FOS: Physical sciences, 02 engineering and technology, Perturbation theory, Kinetic energy, 01 natural sciences, Superconductivity (cond-mat.supr-con), Tetragonal crystal system, High-temperature superconductors, 0103 physical sciences, Independent electron approximation, Anharmonic lattice dynamics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, Electronic band structure, Free-electron model, Physics, [PHYS]Physics [physics], Condensed Matter - Materials Science, Condensed matter physics, Condensed Matter - Superconductivity, Anharmonicity, Materials Science (cond-mat.mtrl-sci), Electron-phonon coupling, Elemental materials, 021001 nanoscience & nanotechnology, Molecular vibration, Density functional theory, Linear response theory, 0210 nano-technology, Random phase approximation
Abstract: We present first-principles calculations of metallic atomic hydrogen in the 400–600 GPa pressure range in a tetragonal structure with space group I41/amd, which is predicted to be its first atomic phase. Our calculations show a band structure close to the free-electron-like limit due to the high electronic kinetic energy induced by pressure. Bands are properly described even in the independent electron approximation fully neglecting the electron-electron interaction. Linear-response harmonic calculations show a dynamically stable phonon spectrum with marked Kohn anomalies. Even if the electron-electron interaction has a minor role in the electronic bands, the inclusion of electronic exchange and correlation in the density response is essential to obtain a dynamically stable structure. Anharmonic effects, which are calculated within the stochastic self-consistent harmonic approximation, harden high-energy optical modes and soften transverse acoustic modes up to a 20% in energy. Despite a large impact of anharmonicity has been predicted in several high-pressure hydrides, here the superconducting critical temperature is barely affected by anharmonicity, as it is lowered from its harmonic 318 K value only to 300 K at 500 GPa. We attribute the small impact of anharmonicity on superconductivity to the absence of softened optical modes and the fairly uniform distribution of the electron-phonon coupling among the vibrational modes., The authors acknowledge financial support from the Spanish Ministry of Economy and Competitiveness (FIS2013-48286-C2-2-P), the Department of Education, Universities and Research of the Basque Government and the University of the Basque Country (IT756-13), and French Agence Nationale de la Recherche (Grant No. ANR-13-IS10-0003-01). M.B. is also thankful to the Department of Education, Language Policy and Culture of the Basque Government for a predoctoral fellowship (Grant No. PRE-2014-1-477). Computer facilities were provided by the Donostia Internatinal Physics Center (DIPC).
Published: 2016
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50. Quantum hydrogen-bond symmetrization in the superconducting hydrogen sulfide system

Author: Chris J. Pickard, Richard J. Needs, Francesco Mauri, Matteo Calandra, Yunwei Zhang, Hanyu Liu, Joseph Nelson, Ion Errea, Yanming Ma, Yinwei Li, Pickard, Christopher [0000-0002-9684-5432], Nelson, Joseph [0000-0002-5653-092X], Needs, Richard [0000-0002-5497-9440], Zhang, Yunwei [0000-0001-7856-9190], Apollo - University of Cambridge Repository, Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Department of Materials Science and Metallurgy [Cambridge University] (DMSM), University of Cambridge [UK] (CAM), School of Physics and Electronic Engineering, Jiangsu Normal University (JSNU), Dipartimento di Fisica, Universita di Roma La Sapienza, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Department of Physics and Astronomy [UCL London], University College of London [London] (UCL), and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)
Subjects: Superconductivity, [PHYS]Physics [physics], Multidisciplinary, cond-mat.supr-con, Hydrogen, Condensed matter physics, Hydrogen bond, Ab initio, chemistry.chemical_element, 02 engineering and technology, Electronic structure, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Molecular physics, chemistry, Covalent bond, Condensed Matter::Superconductivity, 0103 physical sciences, Density functional theory, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology, Phase diagram
Abstract: The quantum nature of the proton can crucially affect the structural and physical properties of hydrogen compounds. For example, in the high-pressure phases of H2O, quantum proton fluctuations lead to symmetrization of the hydrogen bond and reduce the boundary between asymmetric and symmetric structures in the phase diagram by 30 gigapascals (ref. 3). Here we show that an analogous quantum symmetrization occurs in the recently discovered sulfur hydride superconductor with a superconducting transition temperature Tc of 203 kelvin at 155 gigapascals--the highest Tc reported for any superconductor so far. Superconductivity occurs via the formation of a compound with chemical formula H3S (sulfur trihydride) with sulfur atoms arranged on a body-centred cubic lattice. If the hydrogen atoms are treated as classical particles, then for pressures greater than about 175 gigapascals they are predicted to sit exactly halfway between two sulfur atoms in a structure with Im3m symmetry. At lower pressures, the hydrogen atoms move to an off-centre position, forming a short H-S covalent bond and a longer H···S hydrogen bond in a structure with R3m symmetry. X-ray diffraction experiments confirm the H3S stoichiometry and the sulfur lattice sites, but were unable to discriminate between the two phases. Ab initio density-functional-theory calculations show that quantum nuclear motion lowers the symmetrization pressure by 72 gigapascals for H3S and by 60 gigapascals for D3S. Consequently, we predict that the Im3m phase dominates the pressure range within which the high Tc was measured. The observed pressure dependence of Tc is accurately reproduced in our calculations for the phase, but not for the R3m phase. Therefore, the quantum nature of the proton fundamentally changes the superconducting phase diagram of H3S.
Published: 2016
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