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19 results on '"Korea Advanced Institute of Science and Technology (KIST)"'

1. Magnesium- and intermetallic alloys-based hydrides for energy storage: modelling, synthesis and properties

Author

Luca Pasquini, Kouji Sakaki, Etsuo Akiba, Mark D Allendorf, Ebert Alvares, Josè R Ares, Dotan Babai, Marcello Baricco, Josè Bellosta von Colbe, Matvey Bereznitsky, Craig E Buckley, Young Whan Cho, Fermin Cuevas, Patricia de Rango, Erika Michela Dematteis, Roman V Denys, Martin Dornheim, J F Fernández, Arif Hariyadi, Bjørn C Hauback, Tae Wook Heo, Michael Hirscher, Terry D Humphries, Jacques Huot, Isaac Jacob, Torben R Jensen, Paul Jerabek, Shin Young Kang, Nathan Keilbart, Hyunjeong Kim, Michel Latroche, F Leardini, Haiwen Li, Sanliang Ling, Mykhaylo V Lototskyy, Ryan Mullen, Shin-ichi Orimo, Mark Paskevicius, Claudio Pistidda, Marek Polanski, Julián Puszkiel, Eugen Rabkin, Martin Sahlberg, Sabrina Sartori, Archa Santhosh, Toyoto Sato, Roni Z Shneck, Magnus H Sørby, Yuanyuan Shang, Vitalie Stavila, Jin-Yoo Suh, Suwarno Suwarno, Le Thi Thu, Liwen F Wan, Colin J Webb, Matthew Witman, ChuBin Wan, Brandon C Wood, Volodymyr A Yartys, UAM. Departamento de Física de Materiales, Pasquini L., Sakaki K., Akiba E., Allendorf M.D., Alvares E., Ares J.R., Babai D., Baricco M., Bellosta Von Colbe J., Bereznitsky M., Buckley C.E., Cho Y.W., Cuevas F., De Rango P., Dematteis E.M., Denys R.V., Dornheim M., Fernandez J.F., Hariyadi A., Hauback B.C., Heo T.W., Hirscher M., Humphries T.D., Huot J., Jacob I., Jensen T.R., Jerabek P., Kang S.Y., Keilbart N., Kim H., Latroche M., Leardini F., Li H., Ling S., Lototskyy M.V., Mullen R., Orimo S.-I., Paskevicius M., Pistidda C., Polanski M., Puszkiel J., Rabkin E., Sahlberg M., Sartori S., Santhosh A., Sato T., Shneck R.Z., Sorby M.H., Shang Y., Stavila V., Suh J.-Y., Suwarno S., Thi Thu L., Wan L.F., Webb C.J., Witman M., Wan C., Wood B.C., Yartys V.A., Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), National Institute of Advanced Industrial Science and Technology [Tokyo] (AIST), Kyushu University [Fukuoka], Sandia National Laboratories [Livermore], Sandia National Laboratories - Corporation, Helmholtz-Zentrum Geesthacht (GKSS), Departamento de Física Aplicada [UAM Madrid], Universidad Autónoma de Madrid (UAM), Ben-Gurion University of the Negev (BGU), Università degli studi di Torino = University of Turin (UNITO), Curtin University [Perth], Planning and Transport Research Centre (PATREC), Korea Advanced Institute of Science and Technology (KIST), Institut de Chimie et des Matériaux Paris-Est (ICMPE), Institut de Chimie du CNRS (INC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (MRS), 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), Institute for Energy Technology (IFE), Institut Teknologi Sepuluh Nopember [Surabaya] (ITS), Lawrence Livermore National Laboratory (LLNL), Max Planck Institute for Intelligent Systems [Tübingen], Max-Planck-Gesellschaft, Université du Québec à Trois-Rivières (UQTR), Aarhus University [Aarhus], Hefei University of Technology (HFUT), University of Nottingham, UK (UON), University of the Western Cape, Tohoku University [Sendai], Military University of Technology, Technion - Israel Institute of Technology [Haifa], Uppsala Universitet [Uppsala], University of Oslo (UiO), Shibaura Institute of Technology, Griffith University [Brisbane], and University of Science and Technology Beijing [Beijing] (USTB)

Subjects
hydrogen storage material, nanostructure, hydrogen storage materials, energy storage, intermetallic alloys, Intermetallics Compounds, Magnesium Compounds, Física, [CHIM.MATE]Chemical Sciences/Material chemistry, General Medicine, intermetallic alloy, magnesium, catalysts, multiscale modelling, Hydrogen Sorption, Titanium Alloys, catalyst
Abstract

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM, Hydrides based on magnesium and intermetallic compounds provide a viable solution to the challenge of energy storage from renewable sources, thanks to their ability to absorb and desorb hydrogen in a reversible way with a proper tuning of pressure and temperature conditions. Therefore, they are expected to play an important role in the clean energy transition and in the deployment of hydrogen as an efficient energy vector. This review, by experts of Task 40 'Energy Storage and Conversion based on Hydrogen' of the Hydrogen Technology Collaboration Programme of the International Energy Agency, reports on the latest activities of the working group 'Magnesium- and Intermetallic alloys-based Hydrides for Energy Storage'. The following topics are covered by the review: multiscale modelling of hydrides and hydrogen sorption mechanisms; synthesis and processing techniques; catalysts for hydrogen sorption in Mg; Mg-based nanostructures and new compounds; hydrides based on intermetallic TiFe alloys, high entropy alloys, Laves phases, and Pd-containing alloys. Finally, an outlook is presented on current worldwide investments and future research directions for hydrogen-based energy storage

Published
2022
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2. Selective electrochemical reduction of nitric oxide to hydroxylamine by atomically dispersed iron catalyst

Author

Wooyul Kim, B. Kim, Geunsu Bae, Frédéric Jaouen, Hyung Suk Oh, Hyungjun Kim, Chang Hyuck Choi, Se-Jun Kim, Stefan Ringe, Donghyun Kim, Haesol Kim, Gwangju Institute of Science and Technology (GIST), Daegu Gyeongbuk Institute of Science and Technology (DGIST), Korea Advanced Institute of Science and Technology (KAIST), Pohang University of Science and Technology (POSTECH), Korea Advanced Institute of Science and Technology (KIST), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), and Sookmyung Women's University , Seoul 04310, Korea.

Subjects
Science, General Physics and Astronomy, chemistry.chemical_element, 02 engineering and technology, Overpotential, 010402 general chemistry, Electrocatalyst, Electrochemistry, 7. Clean energy, 01 natural sciences, Article, General Biochemistry, Genetics and Molecular Biology, Catalysis, Ferrous, chemistry.chemical_compound, Hydroxylamine, [CHIM]Chemical Sciences, Multidisciplinary, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical engineering, chemistry, 13. Climate action, Density functional theory, Electrocatalysis, 0210 nano-technology, Carbon, Faraday efficiency
Abstract

Electrocatalytic conversion of nitrogen oxides to value-added chemicals is a promising strategy for mitigating the human-caused unbalance of the global nitrogen-cycle, but controlling product selectivity remains a great challenge. Here we show iron–nitrogen-doped carbon as an efficient and durable electrocatalyst for selective nitric oxide reduction into hydroxylamine. Using in operando spectroscopic techniques, the catalytic site is identified as isolated ferrous moieties, at which the rate for hydroxylamine production increases in a super-Nernstian way upon pH decrease. Computational multiscale modelling attributes the origin of unconventional pH dependence to the redox active (non-innocent) property of NO. This makes the rate-limiting NO adsorbate state more sensitive to surface charge which varies with the pH-dependent overpotential. Guided by these fundamental insights, we achieve a Faradaic efficiency of 71% and an unprecedented production rate of 215 μmol cm−2 h−1 at a short-circuit mode in a flow-type fuel cell without significant catalytic deactivation over 50 h operation., Electrocatalytic conversion of nitrogen oxides to value-added chemicals is a promising strategy for mitigating the imbalance in the global nitrogen cycle. Here, the authors present iron–nitrogen-doped carbon as an efficient and durable electrocatalyst for selective nitric oxide reduction to hydroxylamine.

Published
2021
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3. Structure analysis of direct sampling method in 3D electromagnetic inverse problem: near- and far-field configuration

Author

Marc Lambert, Sangwoo Kang, Korea Advanced Institute of Science and Technology (KIST), Laboratoire Génie électrique et électronique de Paris (GeePs), and CentraleSupélec-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
Structure analysis, Applied Mathematics, Direct sampling, Mathematical analysis, Near and far field, Direct sampling method, 010103 numerical & computational mathematics, Inverse problem, 01 natural sciences, Computer Science Applications, Theoretical Computer Science, 010101 applied mathematics, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, 3D inverse electromagnetic scattering problem, Orthogonality sampling method, Signal Processing, 0101 mathematics, Spherical Bessel function, Mathematical Physics, Mathematics
Abstract

International audience; In this paper, the structure analysis of the Direct Sampling Method (DSM) in the {3D} electromagnetic inverse scattering problem in both near-field and far-field configurations is carried out. Even though the DSM is known to be a robust, fast, and efficient non-iterative type algorithm to estimate support and shape of unknown inhomogeneities from the knowledge of scattered data in the 2D scalar electromagnetic case, the choice of a proper test polarization dipole since the data are vectorial in the 3D vector case is to be dealt with, since indeed key to the success of {3D} DSM. Here we carefully analyze the indicator function of DSM using the asymptotic formula of the scattered field under a small volume hypothesis of well-separated inhomogeneities. Thanks to it, an analytic formula of the {3D} DSM indicator function is established. The already proposed heuristic method to choose the polarization test dipole is theoretically justified, and new methods developed for better efficiency. Numerical simulations from synthetic and experimental data validate the theoretical results.

Published
2021
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4. Impact of Channel Length on the Operation of Junctionless Transistors With Substrate Biasing

Author

Mireille Mouis, Sylvain Barraud, Dae-Young Jeon, Gerard Ghibaudo, Korea Advanced Institute of Science and Technology (KIST), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Project: 257111,EC:FP7:ICT,FP7-ICT-2009-5,SQWIRE(2010), and Korea Advanced Institute of Science and Technology (KAIST)

Subjects
010302 applied physics, Physics, Equivalent series resistance, Condensed matter physics, Transconductance, Charge (physics), Biasing, Substrate (electronics), Coupling (probability), 01 natural sciences, Electronic, Optical and Magnetic Materials, 0103 physical sciences, Charge carrier, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Realization (systems), ComputingMilieux_MISCELLANEOUS
Abstract

Junctionless transistors (JLTs) have promising advantages such as structural simplicity without p-n-junctions and bulk conduction-based operation for the realization of advanced complementary metal oxide semiconductor (CMOS) technologies. Here the channel-length dependence on the operation of JLTs with substrate biasing ( ${V}_{\text {gb}}$ ) was investigated in detail. Parasitic series resistance ( ${R}_{\text {sd}}$ ) noticeably decreased as ${V}_{\text {gb}}$ increased. In addition, transconductance ( ${g}_{\text {m}}$ ), its derivative ( dg m/ dV gf), and ON-drain current ( ${I}_{ \mathrm{\scriptscriptstyle ON}}$ ) in a short-channel JLT were significantly affected by the ${V}_{\text {gb}}$ -modulated ${R}_{\text {sd}}$ with charge coupling effects. This work provides important information for better understanding and true estimation of intrinsic JLT performance, for practical applications based on polycrystalline Si, III–V semiconductors, and transition metal dichalcogenides (TMDs) nano-materials as well as advanced logic devices.

Published
2021
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5. (La0.7Sr0.3)0.95(Co0.2Fe0.8)O3−δ, nanostructurée et sous-stoechiométrique, pour une activité catalytique améliorée dans les piles à combustible

Author

Celikbilek, Ozden, Thieu, Cam-Anh, Agnese, Fabio, Cali, Eleonora, Lenser, Christian, Menzler, Norbert, Son, Ji-Won, Skinner, Stephen J, Djurado, Elisabeth, Department of Chemistry [Imperial College London], Imperial College London, Matériaux Interfaces ELectrochimie (MIEL), Laboratoire d'Electrochimie et de Physico-chimie des Matériaux et des Interfaces (LEPMI), Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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)-Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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), Center for Energy Materials Research, Korea Institute of Science and Technology (KIST), Hawolgok-dong, Seongbuk-gu, Seoul 02792, Korea, Division of Nano & Information Technology, KIST School, Korea University of Science and Technology (UST), Hawolgok-dong, Seongbuk-gu, Seoul 02792, Korea, Korea Advanced Institute of Science and Technology (KIST), 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), 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), Laboratoire d'Etude des Matériaux par Microscopie Avancée (LEMMA ), Modélisation et Exploration des Matériaux (MEM), 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)-Université Grenoble Alpes (UGA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Department of Materials, Institute of Energy and Climate Research: Materials Synthesis and Processing (IEK-1), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, and Korea Advanced Institute of Science and Technology (KAIST)

Subjects
[CHIM.MATE]Chemical Sciences/Material chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021

6. Optimization of 3-DoF Manipulators’ Parasitic Motion with the Instantaneous Restriction Space-Based Analytic Coupling Relation

Author

Doik Kim, Hassen Nigatu, and Korea Advanced Institute of Science and Technology (KIST)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, Technology, 0209 industrial biotechnology, QH301-705.5, Computer science, parallel manipulator, QC1-999, IRS, [MATH.MATH-DS]Mathematics [math]/Dynamical Systems [math.DS], Motion (geometry), 02 engineering and technology, Workspace, [MATH.MATH-GR]Mathematics [math]/Group Theory [math.GR], parasiticmotion, Constraint algorithm, parasitic motion, 020901 industrial engineering & automation, 0203 mechanical engineering, constraint analysis, Control theory, General Materials Science, Biology (General), [MATH]Mathematics [math], QD1-999, Instrumentation, ComputingMilieux_MISCELLANEOUS, Fluid Flow and Transfer Processes, Coupling, IMS, Physics, Process Chemistry and Technology, General Engineering, Parallel manipulator, Equations of motion, screw theory, Engineering (General). Civil engineering (General), Computer Science Applications, Chemistry, 020303 mechanical engineering & transports, [MATH.MATH-DG]Mathematics [math]/Differential Geometry [math.DG], Screw theory, Minification, TA1-2040, optimization
Abstract

This paper presents a velocity-level approach to optimizing the parasitic motion of 3-degrees of freedom (DoFs) parallel manipulators. To achieve this objective, we first systematically derive an analytical velocity-level parasitic motion equation as a primary step for the optimization. The paper utilizes an analytic structural constraint equation that describes the manipulator’s restriction space to formulate the parasitic motion equation via the task variable coupling relation. Then, the relevant geometric variables are identified from the analytic coupling equation. The Quasi-Newton method is used for the direction-specific minimization, i.e., optimizing either the x-axis or y-axis parasitic motion. The pattern-search algorithm is applied to optimize all parasitic terms from the workspace. The proposed approach equivalently describes the 3-PhRS, 3-PvRS, 3RPS manipulators. Moreover, other manipulators within a similar category can be equivalently expressed by the proposed method. Finally, the paper presents the resulting optimum configurations and numerical simulations to demonstrate the approach.

Published
2021
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7. Combined effects of A-site non-stoichiometry, crystal structure and microstructure for enhanced catalytic activity of (La,Sr)(Co,Fe)O3-δ cathodes for IT-SOFCs

Author

Celikbilek, Ozden, Thieu, Cam-Anh, Agnese, Fabio, Cali, Eleonora, Lenser, Christian, Menzler, Norbert, Son, Ji-Won, Skinner, Stephen J, Djurado, Elisabeth, Imperial College London, Matériaux Interfaces ELectrochimie (MIEL), Laboratoire d'Electrochimie et de Physico-chimie des Matériaux et des Interfaces (LEPMI), Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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)-Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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), Center for Energy Materials Research (KIST), Korea Advanced Institute of Science and Technology (KAIST), Laboratoire d'Etude des Matériaux par Microscopie Avancée (LEMMA ), Modélisation et Exploration des Matériaux (MEM), 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 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)-Université Grenoble Alpes (UGA), Institute for Materials and Processes in Energy Systems (IWV-1), Korea Advanced Institute of Science and Technology (KIST), and Centre for Advanced Structural Ceramics, Department of Materials, Imperial College, London, UK

Subjects
[SPI]Engineering Sciences [physics], [CHIM.MATE]Chemical Sciences/Material chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2020

8. Channel width dependent subthreshold operation of tri-gate junctionless transistors

Author

Mireille Mouis, Sylvain Barraud, Gerard Ghibaudo, Dae-Young Jeon, Korea Advanced Institute of Science and Technology (KAIST), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-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), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Project: 257111,EC:FP7:ICT,FP7-ICT-2009-5,SQWIRE(2010), and Korea Advanced Institute of Science and Technology (KIST)

Subjects
Materials science, 02 engineering and technology, Channel width, 7. Clean energy, 01 natural sciences, law.invention, law, 0103 physical sciences, Materials Chemistry, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Scaling, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, business.industry, Subthreshold conduction, Transistor, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Thermal conduction, Electronic, Optical and Magnetic Materials, Subthreshold swing, Mobile charge, Optoelectronics, 0210 nano-technology, business
Abstract

Junctionless transistors (JLTs) are one of attractive candidates for further scaling down thanks to their promising advantages based on a structural simplicity without PN junctions, and their physical operation is quite different from traditional inversion-mode (IM) transistors. In this paper, we investigated the subthreshold operation of tri-gate JLTs with various effective width (Weff) and compared to that of IM transistors. The on current to off current ratio (Ion/Ioff) and subthreshold swing (SS) of JLTs were varied dramatically as changing Weff. In addition, a better immunity against short channel effects (SCEs) of JLTs was proven. Physical operation mechanism on the subthreshold regime was also discussed in detail with considering distribution of mobile charge carriers, maximum depletion width, full-depletion mode, bulk neutral and surface accumulation conduction.

Published
2020
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9. Elusive Dzyaloshinskii-Moriya interaction in Fe 3 GeTe 2 monolayer

Author

Laref, Slimane, Kim, Kyoung-Whan, Manchon, Aurélien, King Abdullah University of Science and Technology (KAUST), Korea Advanced Institute of Science and Technology (KIST), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Korea Advanced Institute of Science and Technology (KAIST), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics]
Abstract

International audience; Using symmetry analysis and density functional theory calculations, we uncover the nature of Dzyaloshinskii-Moriya interaction in Fe3GeTe2 monolayer. We show that while such an interaction might result in small distortions of the magnetic texture on the short range, on the long range Dzyaloshinskii-Moriya interaction favors in-plane Néel spin-spirals along equivalent directions of the crystal structure. Whereas our results show that the observed Néel skyrmions cannot be explained by the Dzyaloshinskii-Moriya interaction at the monolayer level, they suggest that canted magnetic texture shall arise at the boundary of Fe3GeTe2 nanoflakes or nanoribbons and, most interestingly, that homochiral planar magnetic textures could be stabilized.

Published
2020

10. Analysis of parasitic motion with the constraint embedded Jacobian for a 3-PRS parallel manipulator

Author

Yun Ho Choi, Hassen Nigatu, Doik Kim, and Korea Advanced Institute of Science and Technology (KIST)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, 0209 industrial biotechnology, Computer science, [MATH.MATH-DS]Mathematics [math]/Dynamical Systems [math.DS], Motion (geometry), Bioengineering, 02 engineering and technology, Kinematics, [MATH.MATH-GR]Mathematics [math]/Group Theory [math.GR], Matrix (mathematics), symbols.namesake, 020901 industrial engineering & automation, 0203 mechanical engineering, Control theory, Position (vector), [MATH]Mathematics [math], ComputingMethodologies_COMPUTERGRAPHICS, Mechanical Engineering, Parallel manipulator, Computer Science Applications, Constraint (information theory), 020303 mechanical engineering & transports, [MATH.MATH-DG]Mathematics [math]/Differential Geometry [math.DG], Mechanics of Materials, Time derivative, Jacobian matrix and determinant, symbols
Abstract

International audience; This study derives the equation of parasitic motion of 3-DoFs parallel manipulator from the velocity-level analytic-constraint equation and compares it with a well-known positionlevel geometric method. The velocity-level constraint is formulated based on the extended Jacobian, derived from the instantaneous motion space (IMS) and the instantaneous restriction space (IRS) for free motion and constraint. In contrast, the position-level constraint, adopted in previous studies, is geometrically obtained by analyzing the moving platform and limb motions. The velocity-level analytic-constraint matrix is used to further analyze the task-space motion. In this paper, the procedure of detecting and identifying the parasitic terms from the independent terms is introduced utilizing the property that comes from the virtue of analytic constraint and inverse rate kinematics algorithm. Then, an equation for the constraint-compatible task motion and a coupling relation between the parasitic and independent motions are derived during further analysis. The paper derived the parasitic motion from position constraint, and an algebraic equivalency with the velocity constraint is shown by taking the time derivative of a point-plane position level constraint for comparison. Finally, numerical simulations are provided to validate the proposed approach and demonstrate the effect of the constraints on the given input velocity within the entire rotational workspace.

Published
2021
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11. Epitaxial integration of high-performance quantum-dot lasers on silicon

Author

Arthur C. Gossard, Zeyu Zhang, Chen Shang, Jianan Duan, Yating Wan, Robert W. Herrick, Justin Norman, Jennifer Selvidge, Daehwan Jung, Mario Dumont, Michael Kennedy, Frédéric Grillot, Heming Huang, Songtao Liu, John E. Bowers, University of California [Santa Barbara] (UCSB), University of California, Korea Advanced Institute of Science and Technology (KIST), Télécommunications Optiques (GTO), Laboratoire Traitement et Communication de l'Information (LTCI), Institut Mines-Télécom [Paris] (IMT)-Télécom Paris-Institut Mines-Télécom [Paris] (IMT)-Télécom Paris, Département Communications & Electronique (COMELEC), Télécom ParisTech, Institut Polytechnique de Paris (IP Paris), and Intel Corporation [USA]

Subjects
Silicon photonics, Materials science, Silicon, business.industry, chemistry.chemical_element, Laser, 7. Clean energy, law.invention, [SPI]Engineering Sciences [physics], Laser linewidth, chemistry, Quantum dot, Quantum dot laser, law, Optoelectronics, Wafer, Photonics, business, ComputingMilieux_MISCELLANEOUS
Abstract

Direct epitaxial growth of III-V lasers on silicon provides the most economically favorable means of photonic integration but has traditionally been hindered by poor material quality. Relative to commercialized heterogeneous integration schemes, epitaxial growth reduces complexity and increases scalability by moving to 300 mm wafer diameters. The challenges associated with the crystalline mismatch between III-Vs and Si can be overcome through optimized buffer layers including thermal cyclic annealing and metamorphic layers, which we have utilized to achieve dislocation densities 10,000,000 h). At 60°C, lasers with extrapolated time-to-failure >50,000 h have been demonstrated for >4,000 h of continuous aging. Lasers have also been investigated for their performance under optical feedback and showed no evidence of coherence collapse at back-reflection levels of 100% (minus 10% tap for measurement) due to the ultralow linewidth enhancement factor (αH < 0.2) and high damping of the optimized quantum dot active region.

Published
2020
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12. High-performance mode-locked lasers on silicon (invited)

Author

Liu, Songtao, Wu, Xinru, Norman, Justin, Jung, Daehwan, Dumont, Mario, Shang, Chen, Wan, Yating, Kennedy, M., Dong, Bozhang, Auth, Dominik, Breuer, Stefan, GRILLOT, Frédéric, Chow, Weng, Gossard, Arthur, Bowers, John, University of California [Santa Barbara] (UCSB), University of California, Korea Advanced Institute of Science and Technology (KIST), Télécommunications Optiques (GTO), Laboratoire Traitement et Communication de l'Information (LTCI), Institut Mines-Télécom [Paris] (IMT)-Télécom Paris-Institut Mines-Télécom [Paris] (IMT)-Télécom Paris, Département Communications & Electronique (COMELEC), Télécom ParisTech, Institut Polytechnique de Paris (IP Paris), Technische Universität Darmstadt (TU Darmstadt), and Sandia National Laboratories in Albuquerque, New Mexico, USA

Subjects
[SPI]Engineering Sciences [physics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2020
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13. Algebraic Insight on the Concomitant Motion of 3RPS and 3PRS PKMs

Author

Nigatu, Hassen, Yihun, Yimesker, Korea Advanced Institute of Science and Technology (KIST), and Wichita State University

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, IMS, [MATH.MATH-DG]Mathematics [math]/Differential Geometry [math.DG], IRS, [MATH.MATH-DS]Mathematics [math]/Dynamical Systems [math.DS], PMs, [MATH]Mathematics [math], Parasitic motion, [MATH.MATH-GR]Mathematics [math]/Group Theory [math.GR]
Abstract

International audience; This study presents an algebraic method to detect, count, and identify concomitant motions of parallel robots at the velocity level. The pose and orientation of moving platform of parallel manipulators (PMs) with f-DOF could be commonly described by f possible motion variables on the instantaneous motion space (IMS) and (6 − f) restriction motion variables on the instantaneous restriction space (IRS). However, in some situations, PMs moving platform may accompanied by a concomitant (parasitic) motions along the direction of restriction space. Therefore, the commonly understood one-to-one correspondence between joint space and task space mobility of non-redundant PMs would be compromised. This phenomenon occurred due to the fact that the alignment of screws can change the reciprocal screws while the given screw systems are still maintained. To demonstrate the proposed method, an amplitude-based concomitant motion comparison is performed on two widely utilized lower-mobility parallel mechanisms, 3RPS and 3PRS. The result has shown that for the selected mechanisms, concomitant motion is identical regardless of their difference in joint arrangements in each limbs.

Published
2020
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14. Enhanced catalytic activity of nanostructured, A-site deficient (La 0.7 Sr 0.3 ) 0.95 (Co 0.2 Fe 0.8 )O 3−δ for SOFC cathodes

Author

Cam-Anh Thieu, Elisabeth Djurado, Ji-Won Son, Eleonora Cali, Fabio Agnese, Stephen J. Skinner, Christian Lenser, Norbert H. Menzler, Ozden Celikbilek, Department of Materials, Imperial College London, Matériaux Interfaces ELectrochimie (MIEL ), Laboratoire d'Electrochimie et de Physico-chimie des Matériaux et des Interfaces (LEPMI ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Chimie du CNRS (INC)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Center for Energy Materials Research (KIST), Korea Advanced Institute of Science and Technology (KAIST), Division of Nano & Information Technology (KIST), Korea University of Science and Technology, SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-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), Institute for Materials and Processes in Energy Systems (IWV-1), Korea Advanced Institute of Science and Technology (KIST), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-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)-Centre National de la Recherche Scientifique (CNRS), and Engineering & Physical Science Research Council (EPSRC)

Subjects
Materials science, Oxide, 02 engineering and technology, engineering.material, law.invention, chemistry.chemical_compound, law, Phase (matter), ddc:530, General Materials Science, ComputingMilieux_MISCELLANEOUS, Perovskite (structure), Renewable Energy, Sustainability and the Environment, Spinel, Oxygen transport, 0303 Macromolecular and Materials Chemistry, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Cathode, chemistry, Chemical engineering, engineering, Nanometre, 0210 nano-technology, Stoichiometry
Abstract

Lower operating temperatures (≤650 °C) of solid oxide fuel cells (SOFCs) are sought in order to decrease the system costs and improve material compatibility and durability issues. Here, we report A-site deficient (La0.7Sr0.3)0.95(Co0.2Fe0.8)O3−δ (LSCF) perovskite film as a potential high-performance cathode with microstructural details at the nanometre length scale. This cathode exhibits area specific resistance values of as low as 0.037 and 0.1 Ω cm2 in a symmetrical cell and peak power densities of 1.4 and 1.0 W cm−2 in a Ni/YSZ anode-supported cell at 650 and 600 °C, respectively. These values are among the highest reported data for LSCF-type cathodes. X-ray diffraction and electron microscopy analyses revealed a closely related two-phase perovskite structure for LSCF and a well-dispersed, nanoscale B-site spinel phase (CoFeOx) decorating the LSCF surfaces. Detailed investigations were carried out to correlate the surface to bulk elemental composition changes on the film, the catalytic activity of the spinel phase and the crystal structures of the constituents with the oxygen reduction reaction (ORR) kinetics. The oxygen transport parameters calculated from the electrochemical impedance spectra indicate an increase by one-to-two-orders of magnitude in the oxygen surface-exchange coefficient in comparison to nominally stoichiometric, state-of-the-art La0.6Sr0.4Co0.2Fe0.8O3−δ. Such substantial improvements in the electrode performance were attributed to the catalytically active B-site spinel phase precipitated as a result of the A-site deficiency and to the very high active surface area of the film.

Published
2019
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15. Pleiotropic Mitochondria: The Influence of Mitochondria on Neuronal Development and Disease

Author

Seok-Kyu Kwon, Vidhya Rangaraju, Romain Cartoni, Tommy L. Lewis, Julien Courchet, Elisa Motori, Matteo Bergami, Yusuke Hirabayashi, Max Planck Institute for Brain Research, Max-Planck-Gesellschaft, Oklahoma Medical Research Foundation (OMRF), The University of Tokyo (UTokyo), University Hospital of Cologne [Cologne], Max planck Institute for Biology of Ageing [Cologne], Duke University [Durham], Korea Advanced Institute of Science and Technology (KIST), Institut NeuroMyoGène (INMG), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Korea Advanced Institute of Science and Technology (KAIST), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and Courchet, Julien

Subjects
0301 basic medicine, Neurogenesis, [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, Disease, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, Mitochondrion, Biology, Mitochondrial Dynamics, 03 medical and health sciences, 0302 clinical medicine, Microtubule, Organelle, Animals, Humans, [SDV.BC] Life Sciences [q-bio]/Cellular Biology, ComputingMilieux_MISCELLANEOUS, Calcium metabolism, Neurons, General Neuroscience, Symposium and Mini-Symposium, [SDV.NEU.NB] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, Neurodegenerative Diseases, Cell biology, Mitochondria, 030104 developmental biology, Ultrastructure, 030217 neurology & neurosurgery, Biogenesis
Abstract

Mitochondria play many important biological roles, including ATP production, lipid biogenesis, ROS regulation, and calcium clearance. In neurons, the mitochondrion is an essential organelle for metabolism and calcium homeostasis. Moreover, mitochondria are extremely dynamic and able to divide, fuse, and move along microtubule tracks to ensure their distribution to the neuronal periphery. Mitochondrial dysfunction and altered mitochondrial dynamics are observed in a wide range of conditions, from impaired neuronal development to various neurodegenerative diseases. Novel imaging techniques and genetic tools provide unprecedented access to the physiological roles of mitochondria by visualizing mitochondrial trafficking, morphological dynamics, ATP generation, and ultrastructure. Recent studies using these new techniques have unveiled the influence of mitochondria on axon branching, synaptic function, calcium regulation with the ER, glial cell function, neurogenesis, and neuronal repair. This review provides an overview of the crucial roles played by mitochondria in the CNS in physiological and pathophysiological conditions.

Published
2019
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16. Analysis of Thin Film Parylene-Metal-Parylene Device Based on Mechanical Tensile Strength Measurement

Author

Seonho Seok, Jinseok Kim, Wonsuk Choi, HyungDal Park, Ockchul Kim, Centre de Nanosciences et Nanotechnologies (C2N (UMR_9001)), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), and Korea Advanced Institute of Science and Technology (KIST)

Subjects
Materials science, 010401 analytical chemistry, Delamination, 02 engineering and technology, Substrate (electronics), 021001 nanoscience & nanotechnology, 01 natural sciences, Finite element method, 0104 chemical sciences, [SPI.MAT]Engineering Sciences [physics]/Materials, Modeling and simulation, Cohesive zone model, chemistry.chemical_compound, Parylene, chemistry, FEM (Finite Element Method), Ultimate tensile strength, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Composite material, Thin film, Implantable, 0210 nano-technology, Neural probe
Abstract

International audience; This paper presents an FEM analysis and experiment of parylene-metal-parylene flexible substrate for implantable medical devices. Tensile strength measurement of the parylene-metal-parylene has been carried out and corresponding FEM modeling and simulation has been done to understand its mechanical behaviour. Besides, frequently encountered metal delamination on parylene substrate has been studied based on cohesive zone model of interface between the two materials.

Published
2019

17. Series Resistance Effects on the Back-Gate Biased Operation of Junctionless Transistors (poster)

Author

Daeyoung Jeon, So Jeong Park, Mireille Mouis, Sylvain Barraud, Kim Gyu-Tae, gerard ghibaudo, Korea Advanced Institute of Science and Technology (KIST), Korea University [Seoul], Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Project: 257111,EC:FP7:ICT,FP7-ICT-2009-5,SQWIRE(2010), and Korea Advanced Institute of Science and Technology (KAIST)

Subjects
[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

18. Characterization and Analysis of Metal Adhesion to Parylene Polymer Substrate Using Scotch Tape Test for Peripheral Neural Probe

Author

Seonho Seok, Jinseok Kim, HyungDal Park, Centre de Nanosciences et de Nanotechnologies (C2N), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Korea Advanced Institute of Science and Technology (KIST)

Subjects
neural probe, Materials science, lcsh:Mechanical engineering and machinery, 020209 energy, 02 engineering and technology, Substrate (electronics), Article, [SPI]Engineering Sciences [physics], chemistry.chemical_compound, Parylene, 0202 electrical engineering, electronic engineering, information engineering, Polymer substrate, lcsh:TJ1-1570, Electrical and Electronic Engineering, Composite material, Thin film, FEM, parylene, Mechanical Engineering, Delamination, Adhesion, 021001 nanoscience & nanotechnology, thin film metal, Evaporation (deposition), adhesion, chemistry, Control and Systems Engineering, Electrode, scotch tape test, 0210 nano-technology
Abstract

This paper presents measurement and FEM (Finite Element Method) analysis of metal adhesion force to a parylene substrate for implantable neural probe. A test device composed of 300 nm-thick gold and 30 nm-thick titanium metal electrodes on top of parylene substrate was prepared. The metal electrodes suffer from delamination during wet metal patterning process, thus, CF4 plasma treatment was applied to the parylene substrate before metal deposition. The two thin film metal layers were deposited by e-beam evaporation process. Metal electrodes had 200 &mu, m in width, 300 &mu, m spacing between the metal lines, and 5 mm length as the neural probe. Adhesion force of the metal lines to parylene substrate was measured with scotch tape test. Angle between the scotch tape and the test device substrate changed from 60&deg, to 90&deg, during characterization. Force exerted the scotch tape was recorded as the function of displacement of the scotch tape. It was found that a peak was created in measured force-displacement curve due to metal delamination. Metal adhesion was estimated 1.3 J/m2 by referring to the force peak and metal width at the force-displacement curve. Besides, the scotch tape test was simulated to comprehend delamination behavior of the test through FEM modeling.

Published
2020
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19. Anomalous transport on regular fracture networks: Impact of conductivity heterogeneity and mixing at fracture intersections

Author

Marco Dentz, Peter K. Kang, Ruben Juanes, Tanguy Le Borgne, Massachusetts Institute of Technology (MIT), Korea Advanced Institute of Science and Technology (KIST), Institute of Environmental Assessment and Water Research (IDAEA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Transferts d'eau et de matière dans les milieux hétérogènes complexes, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), European Research Council, Korea Advanced Institute of Science and Technology (KAIST), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Lagrange multipliers, Stochastic modelling, Monte Carlo method, Conductivity, Models, Theoretical, Markov Chains, Physics::Geophysics, Solutions, Transverse plane, Motion, Hydraulic conductivity, Fracture (geology), Computer Simulation, Statistical physics, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], Fracture network, Non-fickian transports, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, Scaling, Monte Carlo Method, Mixing (physics), Lagrangian velocity
Abstract

We investigate transport on regular fracture networks that are characterized by heterogeneity in hydraulic conductivity. We discuss the impact of conductivity heterogeneity and mixing within fracture intersections on particle spreading. We show the emergence of non-Fickian transport due to the interplay between the network conductivity heterogeneity and the degree of mixing at nodes. Specifically, lack of mixing at fracture intersections leads to subdiffusive scaling of transverse spreading but has negligible impact on longitudinal spreading. An increase in network conductivity heterogeneity enhances both longitudinal and transverse spreading and leads to non-Fickian transport in longitudinal direction. Based on the observed Lagrangian velocity statistics, we develop an effective stochastic model that incorporates the interplay between Lagrangian velocity correlation and velocity distribution. The model is parameterized with a few physical parameters and is able to capture the full particle transition dynamics. © 2015 American Physical Society., PKK and RJ acknowledge the support of the US Department of Energy (grant DE-SC0003907), and a MISTI Global Seed Funds award. MD acknowledges the support of the European Research Council (ERC) through the project MHetScale (617511). TLB acknowledges the support of the INTERREG IV project CLIMAWAT. The data to reproduce the work can be obtained from the corresponding author

Published
2015
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