2,799 results on '"Rodolakis, A."'
Search Results
2. High-Resolution Full-field Structural Microscopy of the Voltage Induced Filament Formation in Neuromorphic Devices
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Kisiel, Elliot, Salev, Pavel, Poudyal, Ishwor, Baptista, Fellipe, Rodolakis, Fanny, Zhang, Zhan, Shpyrko, Oleg, Schuller, Ivan K., Islam, Zahir, and Frano, Alex
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Physics - Applied Physics ,Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Neuromorphic functionalities in memristive devices are commonly associated with the ability to electrically create local conductive pathways by resistive switching. The archetypal correlated material, VO2, has been intensively studied for its complex electronic and structural phase transition as well as its filament formation under applied voltages. Local structural studies of the filament behavior are often limited due to time-consuming rastering which makes impractical many experiments aimed at investigating large spatial areas or temporal dynamics associated with the electrical triggering of the phase transition. Utilizing Dark Field X-ray Microscopy (DFXM), a novel full-field x-ray imaging technique, we study this complex filament formation process in-operando in VO2 devices from a structural perspective. We show that prior to filament formation, there is a significant gain of the metallic rutile phase beneath the metal electrodes that define the device. We observed that the filament formation follows a preferential path determined by the nucleation sites within the device. These nucleation sites are predisposed to the phase transition and can persistently maintain the high-temperature rutile phase even after returning to room temperature, which can enable a novel training/learning mechanism. Filament formation also appears to follow a preferential path determined by a nucleation site within the device which is predisposed to the rutile transition even after returning to room temperature. Finally, we found that small isolated low-temperature phase clusters can be present inside the high-temperature filaments indicating that the filament structure is not uniform. Our results provide a unique perspective on the electrically induced filament formation in metal-insulator transition materials, which further the basic understanding of this resistive switching., Comment: 29 pages, 10 figures; 19 pages main text, 3 figures; 10 pages Supplementary material, 7 figures
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- 2023
3. Lower Urinary Tract Symptoms in Greek Women After Menopause: The LADY Study
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Lambrinoudaki, Irene, Mili, Nikoletta, Augoulea, Areti, Armeni, Eleni, Vakas, Panagiotis, Panoulis, Konstantinos, Vlahos, Nikolaos, Mikos, Themistoklis, Grimbizis, Grigorios, Rodolakis, Alexandros, and Athanasiou, Stavros
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- 2024
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4. Chemotherapy response score as a predictor of survival in ovarian cancer patients
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Rodolakis, Ioannis, Liontos, Michalis, Pergialiotis, Vasilios, Haidopoulos, Dimitrios, Kaparelou, Maria, Efthimios Vlachos, Dimitrios, Dimopoulos, Meletios Athanasios, Loutradis, Dimitrios, Rodolakis, Alexandros, Bamias, Aristotelis, and Thomakos, Nikolaos
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- 2024
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5. Quasiparticle characteristics of the weakly ferromagnetic Hund's metal MnSi
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Fang, Yuan, Zhang, Huali, Wang, Ding, Yang, Guowei, Wu, Yi, Li, Peng, Xiao, Zhiguang, Lin, Tianyun, Zheng, Hao, Li, Xiao-Long, Wang, Huan-Hua, Rodolakis, Fanny, Song, Yu, Wang, Yilin, Cao, Chao, and Liu, Yang
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Condensed Matter - Strongly Correlated Electrons - Abstract
Hund's metals are multi-orbital systems with $3d$ or $4d$ electrons exhibiting both itinerant character and local moments, and they feature Kondo-like screenings of local orbital and spin moments, with suppressed coherence temperature driven by Hund's coupling $J_H$. They often exhibit magnetic order at low temperature, but how the interaction between the Kondo-like screening and long-range magnetic order is manifested in the quasiparticle spectrum remains an open question. Here we present spectroscopic signature of such interaction in a Hund's metal candidate MnSi exhibiting weak ferromagnetism. Our photoemission measurements reveal renormalized quasiparticle bands near the Fermi level with strong momentum dependence: the ferromagnetism manifests through possibly exchange-split bands (Q1) below $T_C$ , while the spin/orbital screenings lead to gradual development of quasiparticles (Q2) upon cooling. Our results demonstrate how the characteristic spin/orbital coherence in a Hund's metal could coexist and compete with the magnetic order to form a weak itinerant ferromagnet, via quasiparticle bands that are well separated in momentum space and exhibit distinct temperature dependence. Our results imply that the competition between the spin/orbital screening and the magnetic order in a Hund's metal bears intriguing similarity to the Kondo lattice systems., Comment: accepted by PRB
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- 2022
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6. Structural Chirality of Polar Skyrmions Probed by Resonant Elastic X-Ray Scattering
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McCarter, Margaret R, Kim, Kook Tae, Stoica, Vladimir A, Das, Sujit, Klewe, Christoph, Donoway, Elizabeth P, Burn, David M, Shafer, Padraic, Rodolakis, Fanny, Gonçalves, Mauro AP, Gómez-Ortiz, Fernando, Íñiguez, Jorge, García-Fernández, Pablo, Junquera, Javier, Lovesey, Stephen W, van der Laan, Gerrit, Park, Se Young, Freeland, John W, Martin, Lane W, Lee, Dong Ryeol, and Ramesh, Ramamoorthy
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Physical Sciences ,Condensed Matter Physics ,Mathematical Sciences ,Engineering ,General Physics ,Mathematical sciences ,Physical sciences - Abstract
An escalating challenge in condensed-matter research is the characterization of emergent order-parameter nanostructures such as ferroelectric and ferromagnetic skyrmions. Their small length scales coupled with complex, three-dimensional polarization or spin structures makes them demanding to trace out fully. Resonant elastic x-ray scattering (REXS) has emerged as a technique to study chirality in spin textures such as skyrmions and domain walls. It has, however, been used to a considerably lesser extent to study analogous features in ferroelectrics. Here, we present a framework for modeling REXS from an arbitrary arrangement of charge quadrupole moments, which can be applied to nanostructures in materials such as ferroelectrics. With this, we demonstrate how extended reciprocal space scans using REXS with circularly polarized x rays can probe the three-dimensional structure and chirality of polar skyrmions. Measurements, bolstered by quantitative scattering calculations, show that polar skyrmions of mixed chirality coexist, and that REXS allows valuation of relative fractions of right- and left-handed skyrmions. Our quantitative analysis of the structure and chirality of polar skyrmions highlights the capability of REXS for establishing complex topological structures toward future application exploits.
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- 2022
7. Possible strain-induced enhancement of the superconducting onset transition temperature in infinite-layer nickelates
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Xiaolin Ren, Jiarui Li, Wei-Chih Chen, Qiang Gao, Joshua J. Sanchez, Jordyn Hales, Hailan Luo, Fanny Rodolakis, Jessica L. McChesney, Tao Xiang, Jiangping Hu, Riccardo Comin, Yao Wang, Xingjiang Zhou, and Zhihai Zhu
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Astrophysics ,QB460-466 ,Physics ,QC1-999 - Abstract
Abstract The mechanism of unconventional superconductivity in correlated materials remains a great challenge in condensed matter physics. The recent discovery of superconductivity in infinite-layer nickelates, as an analog to high-T c cuprates, has opened a new route to tackle this challenge. By growing 8 nm Pr0.8Sr0.2NiO2 films on the (LaAlO3)0.3(Sr2AlTaO6)0.7 substrate, we successfully raise the superconducting onset transition temperature T c in the widely studied SrTiO3-substrated nickelates from 9 K into 15 K, which indicates compressive strain is an efficient protocol to further enhance superconductivity in infinite-layer nickelates. Additionally, the x-ray absorption spectroscopy, combined with the first-principles and many-body simulations, suggest a crucial role of the hybridization between Ni and O orbitals in the unconventional pairing. These results also suggest the increase of T c be driven by the change of charge-transfer nature that would narrow the origin of general unconventional superconductivity in correlated materials to the covalence of transition metals and ligands.
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- 2023
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8. Controversies and Advances in the Personalized Surgical Treatment of Cervical Cancer
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Vasilios Pergialiotis, Ioannis Rodolakis, Alexandros Rodolakis, and Nikolaos Thomakos
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cervical cancer ,personalized treatment ,survival outcomes ,novel approaches ,Medicine - Abstract
Cervical cancer represents a global health issue as it is mostly encountered in women of reproductive age, while at the same time, survival outcomes seem to have remained constant during the last two decades. The need to implement fertility-sparing strategies as well as to decrease the morbidity that accompanies radical treatment has been extensively studied. During the last decade, several randomized clinical trials have been released, resulting in significant advances in the surgical treatment of early-stage disease. At the same time, evidence about the surgical treatment of advanced-stage disease as well as recurrent disease has gradually appeared and seems to be promising, thus leading the point forward towards personalized medicine that will remove the surgical barriers that seem concrete in our era. Nevertheless, the discrepancies in perioperative morbidity and survival outcomes that were observed among published studies raise several questions. In the present article, we chose to review the gray fields in the surgical treatment of early-stage and advanced-stage cervical cancer. Studies that are based on strong evidence that support current clinical practice are compared to smaller cohorts that present novel data that may form the basis for future research, and issues that remain poorly explored are discussed in an effort to help establish a consensus for future research development.
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- 2024
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9. Stabilization of three-dimensional charge order through interplanar orbital hybridization in Pr$_x$Y$_{1-x}$Ba$_2$Cu$_3$O$_{6+\delta}$
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Ruiz, Alejandro, Gunn, Brandon, Lu, Yi, Sasmal, Kalyan, Moir, Camilla M., Basak, Rourav, Huang, Hai, Lee, Jun-Sik, Rodolakis, Fanny, Boyle, Timothy J., Walker, Morgan, He, Yu, Blanco-Canosa, Santiago, Neto, Eduardo H. da Silva, Maple, M. Brian, and Frano, Alex
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Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Superconductivity - Abstract
The shape of 3$d$-orbitals often governs the electronic and magnetic properties of correlated transition metal oxides. In the superconducting cuprates, the planar confinement of the $d_{x^2-y^2}$ orbital dictates the two-dimensional nature of the unconventional superconductivity and a competing charge order. Achieving orbital-specific control of the electronic structure to allow coupling pathways across adjacent planes would enable direct assessment of the role of dimensionality in the intertwined orders. Using Cu-$L_3$ and Pr-$M_5$ resonant x-ray scattering and first-principles calculations, we report a highly correlated three-dimensional charge order in Pr-substituted YBa$_2$Cu$_3$O$_{7}$, where the Pr $f$-electrons create a direct orbital bridge between CuO$_2$ planes. With this, we demonstrate that interplanar orbital engineering can be used to surgically control electronic phases in correlated oxides and other layered materials.
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- 2022
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10. Possible strain-induced enhancement of the superconducting onset transition temperature in infinite-layer nickelates
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Ren, Xiaolin, Li, Jiarui, Chen, Wei-Chih, Gao, Qiang, Sanchez, Joshua J., Hales, Jordyn, Luo, Hailan, Rodolakis, Fanny, McChesney, Jessica L., Xiang, Tao, Hu, Jiangping, Comin, Riccardo, Wang, Yao, Zhou, Xingjiang, and Zhu, Zhihai
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- 2023
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11. Electronic structure of superconducting nickelates probed by resonant photoemission spectroscopy
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Chen, Zhuoyu, Osada, Motoki, Li, Danfeng, Been, Emily M, Chen, Su-Di, Hashimoto, Makoto, Lu, Donghui, Mo, Sung-Kwan, Lee, Kyuho, Wang, Bai Yang, Rodolakis, Fanny, McChesney, Jessica L, Jia, Chunjing, Moritz, Brian, Devereaux, Thomas P, Hwang, Harold Y, and Shen, Zhi-Xun
- Abstract
The discovery of infinite-layer nickelate superconductors has spurred enormous interest. While the Ni1+ cations possess nominally the same 3d9 configuration as Cu2+ in cuprates, the electronic structure variances remain elusive. Here, we present a soft X-ray photoemission spectroscopy study on parent and doped infinite-layer Pr-nickelate thin films with a doped perovskite reference. By identifying the Ni character with resonant photoemission and comparison with density functional theory + U (on-site Coulomb repulsion energy) calculations, we estimate U ∼5 eV, smaller than the charge transfer energy Δ ∼8 eV, confirming the Mott-Hubbard electronic structure in contrast to charge-transfer cuprates. Near the Fermi level (EF), we observe a signature of occupied rare-earth states in the parent compound, which is consistent with a self-doping picture. Our results demonstrate a correlation between the superconducting transition temperature and the oxygen 2p hybridization near EF when comparing hole-doped nickelates and cuprates.
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- 2022
12. Strain-induced enhancement of $T_c$ in infinite-layer Pr$_{0.8}$Sr$_{0.2}$NiO$_2$ films
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Ren, Xiaolin, Li, Jiarui, Chen, Wei-Chih, Gao, Qiang, Sanchez, Joshua J., Hales, Jordyn, Luo, Hailan, Rodolakis, Fanny, McChesney, Jessica L., Xiang, Tao, Hu, Jiangping, Zhang, Fu-Chun, Comin, Riccardo, Wang, Yao, Zhou, X. J., and Zhu, Zhihai
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Condensed Matter - Superconductivity - Abstract
The mechanism of unconventional superconductivity in correlated materials remains a great challenge in condensed matter physics. The recent discovery of superconductivity in infinite-layer nickelates, as analog to high-Tc cuprates, has opened a new route to tackle this challenge. By growing 8 nm Pr0.8Sr0.2NiO2 films on the (LaAlO3)0.3(Sr2AlTaO6)0.7 substrate, we successfully raise the transition temperature Tc from 9 K in the widely studied SrTiO3-substrated nickelates into 15 K. By combining x-ray absorption spectroscopy with the first-principles and many-body simulations, we find a positive correlation between Tc and the pre-edge peak intensity, which can be attributed to the hybridization between Ni and O orbitals induced by the strain. Our result suggests that structural engineering can further enhance unconventional superconductivity, and the charge-transfer property plays a crucial role in the pairing strength., Comment: 8 pages, 4 figures
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- 2021
13. Diaphragmatic stripping in epithelial ovarian cancer at first diagnosis: Impact on morbidity and survival outcomes
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Pergialiotis, Vasilios, Feroussis, Loukas, Papadatou, Konstantina, Vlachos, Dimitrios Efthymios, Aggelou, Kyveli, Rodolakis, Ioannis, Alexakis, Nikolaos, Bramis, Konstantinos, Daskalakis, Georgios, Thomakos, Nikolaos, and Haidopoulos, Dimitrios
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- 2024
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14. Electronic structure of superconducting nickelates probed by resonant photoemission spectroscopy
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Chen, Zhuoyu, Osada, Motoki, Li, Danfeng, Been, Emily M., Chen, Su-Di, Hashimoto, Makoto, Lu, Donghui, Mo, Sung-Kwan, Lee, Kyuho, Wang, Bai Yang, Rodolakis, Fanny, McChesney, Jessica L., Jia, Chunjing, Moritz, Brian, Devereaux, Thomas P., Hwang, Harold Y., and Shen, Zhi-Xun
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Condensed Matter - Superconductivity ,Condensed Matter - Strongly Correlated Electrons - Abstract
The discovery of infinite-layer nickelate superconductors has spurred enormous interest. While the Ni$^{1+}$ cations possess nominally the same 3$d^9$ configuration as Cu$^{2+}$ in cuprates, the electronic structure variances remain elusive. Here, we present a soft x-ray photoemission spectroscopy study on parent and doped infinite-layer Pr-nickelate thin films with a doped perovskite reference. By identifying the Ni character with resonant photoemission and comparison to density functional theory + U (on-site Coulomb repulsion energy) calculations, we estimate U ~5 eV, smaller than the charge transfer energy $\Delta$ ~8 eV, confirming the Mott-Hubbard electronic structure in contrast to charge-transfer cuprates. Near the Fermi level ($E_F$), we observe a signature of occupied rare-earth states in the parent compound, which is consistent with a self-doping picture. Our results demonstrate a correlation between the superconducting transition temperature and the oxygen 2$p$ hybridization near $E_F$ when comparing hole-doped nickelates and cuprates., Comment: 28 pages, 10 figures
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- 2021
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15. Chiral structures of electric polarization vectors quantified by X-ray resonant scattering
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Kim, Kook Tae, McCarter, Margaret R, Stoica, Vladimir A, Das, Sujit, Klewe, Christoph, Donoway, Elizabeth P, Burn, David M, Shafer, Padraic, Rodolakis, Fanny, Gonçalves, Mauro AP, Gómez-Ortiz, Fernando, Íñiguez, Jorge, García-Fernández, Pablo, Junquera, Javier, Susarla, Sandhya, Lovesey, Stephen W, van der Laan, Gerrit, Park, Se Young, Martin, Lane W, Freeland, John W, Ramesh, Ramamoorthy, and Lee, Dong Ryeol
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Chemical Sciences ,Physical Sciences ,Condensed Matter Physics - Abstract
Resonant elastic X-ray scattering (REXS) offers a unique tool to investigate solid-state systems providing spatial knowledge from diffraction combined with electronic information through the enhanced absorption process, allowing the probing of magnetic, charge, spin, and orbital degrees of spatial order together with electronic structure. A new promising application of REXS is to elucidate the chiral structure of electrical polarization emergent in a ferroelectric oxide superlattice in which the polarization vectors in the REXS amplitude are implicitly described through an anisotropic tensor corresponding to the quadrupole moment. Here, we present a detailed theoretical framework and analysis to quantitatively analyze the experimental results of Ti L-edge REXS of a polar vortex array formed in a PbTiO3/SrTiO3 superlattice. Based on this theoretical framework, REXS for polar chiral structures can become a useful tool similar to x-ray resonant magnetic scattering (XRMS), enabling a comprehensive study of both electric and magnetic REXS on the chiral structures.
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- 2022
16. Search for $Q \sim 0$ order near a forbidden Bragg position in Bi$_{2.1}$Sr$_{1.9}$CaCu$_2$O$_{8+x}$ with resonant soft x-ray scattering
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Guo, Xuefei, Lee, Sangjun, Johnson, Thomas A., Chen, Jin, Vandeventer, Paul, Husain, Ali A., Rodolakis, Fanny, McChesney, Jessica L., Shafer, Padraic, Huang, Hai, Lee, Jun-Sik, Schneeloch, John, Zhong, Ruidan, Gu, G. D., Mitrano, Matteo, and Abbamonte, Peter
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Condensed Matter - Strongly Correlated Electrons - Abstract
Identifying what broken symmetries are present in the cuprates has become a major area of research. Many authors have reported evidence for so-called "$Q \sim 0$" order that involves broken inversion, mirror, chiral, or time-reversal symmetry that is uniform in space. Not all these observations are well understood and new experimental probes are needed. Here we use resonant soft x-ray scattering (RSXS) to search for $Q \sim 0$ order in Bi$_{2.1}$Sr$_{1.9}$CaCu$_2$O$_{8+x}$ (Bi-2212) by measuring the region of a forbidden Bragg peak, $(0,0,3)$, which is normally extinguished by symmetry but may become allowed on resonance if valence band order is present. Using circularly polarized light, we found that this reflection becomes allowed on the Cu $L_3$ resonance for temperatures $T_c < T < T^\ast$, though remains absent in linear polarization and at other temperatures. This observation suggests the existence of spatially uniform valence band order near the pseudogap temperature. In addition, we observed periodic oscillations in the specular reflectivity from the sample surface that resemble thin film interference fringes, though no known film is present. These fringes are highly resonant, appear in all polarizations, and exhibit a period that depends on the location where the beam strikes the sample surface. We speculate that these fringes arise from interaction between some intrinsic valence band instability and extrinsic structural surface morphologies of the material. Our study supports the existence of some kind of $Q \sim 0$ broken symmetry state in Bi-2212 at intermediate temperatures, and calls for further study using a microfocused beam that could disentangle microscopic effects from macroscopic heterogeneities., Comment: 9 pages, 4 figures
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- 2021
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17. Controversies and Advances in the Personalized Surgical Treatment of Cervical Cancer
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Pergialiotis, Vasilios, primary, Rodolakis, Ioannis, additional, Rodolakis, Alexandros, additional, and Thomakos, Nikolaos, additional
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- 2024
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18. Search for Q ∼ 0 Order near a Forbidden Bragg Position in Bi2.1Sr1.9CaCu2O8+x with Resonant Soft X-ray Scattering
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Guo, Xuefei, Lee, Sangjun, Johnson, Thomas A, Chen, Jin, Vandeventer, Paul, Husain, Ali A, Rodolakis, Fanny, McChesney, Jessica L, Shafer, Padraic, Huang, Hai, Lee, Jun-Sik, Schneeloch, John, Zhong, Ruidan, Gu, Genda, Mitrano, Matteo, and Abbamonte, Peter
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Physical Sciences ,Condensed Matter Physics ,Mathematical Sciences ,General Physics ,Mathematical sciences ,Physical sciences - Abstract
Identifying what broken symmetries are present in the cuprates has become a major area of research. Many authors have reported evidence for so-called "Q ∼ 0"order that involves broken inversion, mirror, chiral, or time-reversal symmetry that is uniform in space. Not all these observations are well understood and new experimental probes are needed. Here we use resonant soft x-ray scattering (RSXS) to search for Q ∼ 0 order in Bi2.1Sr1.9CaCu2O8+x (Bi-2212) by measuring the region of a forbidden Bragg peak, 0; 0; 3 , which is normally extinguished by symmetry but may become allowed on resonance if valence band order is present. Using circularly polarized light, we found that this reflection becomes allowed on the Cu L3 resonance for temperatures Tc < T < T+, though remains absent in linear polarization and at other temperatures. This observation suggests the existence of spatially uniform valence band order near the pseudogap temperature. In addition, we observed periodic oscillations in the specular reflectivity from the sample surface that resemble thin film interference fringes, though no known film is present. These fringes are highly resonant, appear in all polarizations, and exhibit a period that depends on the location where the beam strikes the sample surface. We speculate that these fringes arise from interaction between some intrinsic valence band instability and extrinsic structural surface morphologies of the material. Our study supports the existence of some kind of Q ∼ 0 broken symmetry state in Bi-2212 at intermediate temperatures. Further studies using a microfocused beam, which could disentangle microscopic effects from macroscopic heterogeneities, are needed to ascertain the universality of the effect.
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- 2021
19. Giant anisotropic magnetoresistance with dual-four-fold symmetry in CaMnO3/CaIrO3 heterostructures
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Sardar, Suman, Vagadia, Megha, Das, Tejas Tank Sarmistha, Gunn, Brandon, Pandey, Parul, Hübner, R., Rodolakis, Fanny, Fabbris, Gilberto, Choi, Yongseong, Haskel, Daniel, Frano, Alex, and Rana, D. S.
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Condensed Matter - Materials Science - Abstract
The realization of four-fold anisotropic magnetoresistance (AMR) in novel 3d-5d heterostructures has boosted major efforts in antiferromagnetic spintronics. However, despite the potential of incorporating strong spin-orbit coupling, only small AMR signals have been detected thus far, prompting a search for new mechanisms to enhance the signal. In this study on CaMnO3/CaIrO3 heterostructures, we report a unique dual-four-fold symmetric 70% AMR; a signal two orders of magnitude larger than previously observed in similar systems. We find that one order is enhanced by tuning a large biaxial anisotropy through octahedral tilts of similar sense in the constituent layers, while the second order is triggered by a spin-flop transition in a nearly Mott-type phase. Dynamics between these two phenomena as evidenced by the step-like AMR and a superimposed biaxial-anisotropy-induced AMR capture a subtle interplay of pseudospin coupling with the lattice and external magnetic field. Our study shows that a combination of charge-transfer, interlayer coupling, and a spin-flop transition can yield a giant AMR relevant for sensing and antiferromagnetic memory applications.
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- 2020
20. Soft x-ray detection for small satellites with a commercial CMOS sensor at room temperature
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Tammes, Steve, Roth, Tyler, Kaaret, Philip, DeRoo, Casey, Elmaleh, Abdallah, McChesney, Jessica L, and Rodolakis, Fanny
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Physics - Instrumentation and Detectors ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Recently CMOS (complementary metal-oxide semiconductor) sensors have progressed to a point where they may offer improved performance in imaging x-ray detection compared to the CCDs often used in x-ray satellites. We demonstrate x-ray detection in the soft x-ray band (250-1700 eV) by a commercially available back-illuminated Sony IMX290LLR CMOS sensor using the Advanced Photon Source at the Argonne National Laboratory. While operating the device at room temperature, we measure energy resolutions (FWHM) of 48 eV at 250 eV and 83 eV at 1700 eV which are comparable to the performance of the Chandra ACIS and the Suzaku XIS. Furthermore, we demonstrate that the IMX290LLR can withstand radiation up to 17.1 krad, making it suitable for use on spacecraft in low earth orbit.
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- 2020
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21. Lower Limb Lymphedema Awareness among Gynecological Cancer Patients: An International Survey Supported by the European Network of Gynecological Cancer Advocacy Groups (ENGAGe) Group
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Dimitrios Haidopoulos, Vasilios Pergialiotis, Maria Papageorgiou, Michael J. Halaska, Katerina Maxova, Elena Ulrich, Ignacio Zapardiel, Alexandros Rodolakis, Murat Gultekin, and Christina Fotopoulou
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lymphedema ,gynecologic oncology ,cancer ,patient awareness ,electronic survey ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Introduction: Patient awareness of postoperative lymphedema in the field of gynecologic oncology has been poorly documented in the international literature. We wished to capture and document the awareness among gynecological cancer survivors about postoperative lymphedema, including aspects such as the adequacy of perioperative counseling, management, and quality of life. Methods: A web-based survey comprising 25 multiple-choice questions was distributed to gynecological cancer advocacy groups within the European Network of Gynecological Cancer Advocacy Groups (ENGAGe) group. The survey was validated in a pilot group of gynecological patients prior to distribution. Results: Overall, 386 women from 20 countries completed the questionnaire. Only half of the patients (n = 211) knew what lymphedema is, whereas 52% of the respondents stated that they were never informed at their pre-operative assessment about the potential risk of developing lymphedema. Fifty-three percent of those women who were informed about the risk and management of lymphedema received information through self-initiative, connecting mainly with patient groups or online. Approximately 84% of patients with lymphedema reported that they informed their doctor about their symptoms. Ninety-four patients (55.3%, which is not 55% of the 386) were treated for lymphedema. Forty-five women out of 136 reported that lymphedema significantly affected their everyday lives. Discussion: We report a large lack of awareness and a significant gap of knowledge about the risks and treatment options related to postoperative lymphedema among gynecological cancer survivors. Institutional practice routines and awareness among professionals need to be urgently recalled and adapted to adequately inform and support gynecological cancer patients.
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- 2024
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22. Electronic correlations in the semiconducting half-Heusler compound FeVSb
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Shourov, Estiaque H., Strohbeen, Patrick J., Du, Dongxue, Sharan, Abhishek, de Lima, Felipe C., Rodolakis, Fanny, McChesney, Jessica, Yannello, Vincent, Janotti, Anderson, Birol, Turan, and Kawasaki, Jason K.
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Condensed Matter - Materials Science - Abstract
Electronic correlations are crucial to the low energy physics of metallic systems with localized $d$ and $f$ states; however, their effect on band insulators and semiconductors is typically negligible. Here, we measure the electronic structure of the half-Heusler compound FeVSb, a band insulator with filled shell configuration of 18 valence electrons per formula unit ($s^2 p^6 d^{10}$). Angle-resolved photoemission spectroscopy (ARPES) reveals a mass renormalization of $m^{*}/m_{bare}= 1.4$, where $m^{*}$ is the measured effective mass and $m_{bare}$ is the mass from density functional theory (DFT) calculations with no added on-site Coulomb repulsion. Our measurements are in quantitative agreement with dynamical mean field theory (DMFT) calculations, highlighting the many-body origin of the mass renormalization. This mass renormalization lies in dramatic contrast to other filled shell intermetallics, including the thermoelectric materials CoTiSb and NiTiSn; and has a similar origin to that in FeSi, where Hund's coupling induced fluctuations across the gap can explain a dynamical self-energy and correlations. Our work calls for a re-thinking of the role of correlations and Hund's coupling in intermetallic band insulators.
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- 2020
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23. Band Engineering of Dirac Semimetals using Charge Density Waves
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Lei, Shiming, Teicher, Samuel M. L., Topp, Andreas, Cai, Kehan, Lin, Jingjing, Rodolakis, Fanny, McChesney, Jessica L., Krivenkov, Maxim, Marchenko, Dmitry, Varykhalov, Andrei, Ast, Christian R., Car, Roberto, Cano, Jennifer, Vergniory, Maia G., Ong, N. Phuan, and Schoop, Leslie M.
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Condensed Matter - Materials Science ,Condensed Matter - Strongly Correlated Electrons - Abstract
New developments in the field of topological matter are often driven by materials discovery, including novel topological insulators, Dirac semimetals and Weyl semimetals. In the last few years, large efforts have been performed to classify all known inorganic materials with respect to their topology. Unfortunately, a large number of topological materials suffer from non-ideal band structures. For example, topological bands are frequently convoluted with trivial ones, and band structure features of interest can appear far below the Fermi level. This leaves just a handful of materials that are intensively studied. Finding strategies to design new topological materials is a solution. Here we introduce a new mechanism that is based on charge density waves and non-symmorphic symmetry to design an idealized Dirac semimetal. We then show experimentally that the antiferromagnetic compound GdSb$_{0.46}$Te$_{1.48}$ is a nearly ideal Dirac semimetal based on the proposed mechanism, meaning that most interfering bands at the Fermi level are suppressed. Its highly unusual transport behavior points to a thus far unknown regime, in which Dirac carriers with Fermi energy very close to the node seem to gradually localize in the presence of lattice and magnetic disorder.
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- 2020
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24. The effect of the delivery mode on the evolution of cervical intraepithelial lesions during pregnancy. A meta-analysis
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Douligeris, Athanasios, Pergialiotis, Vasilios, Pappa, Kalliopi, Mortaki, Anastasia, Pittokopitou, Savia, Rodolakis, Ioannis, Papapanagiotou, Angeliki, Rodolakis, Alexandros, and Daskalakis, George
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- 2022
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25. High electrical conductivity in the epitaxial polar metals LaAuGe and LaPtSb
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Du, Dongxue, Lim, Amber, Zhang, Chenyu, Strohbeen, Patrick J., Shourov, Estiaque H., Rodolakis, Fanny, McChesney, Jessica L., Voyles, Paul, Fredrickson, Daniel C., and Kawasaki, Jason K.
- Subjects
Condensed Matter - Materials Science - Abstract
Polar metals are an intriguing class of materials that simultaneously host free carriers and polar structural distortions. Despite the name "polar metal," however, most well-studied polar metals are poor electrical conductors. Here, we demonstrate the molecular beam epitaxial (MBE) growth of LaPtSb and LaAuGe, two polar metal compounds whose electrical resistivity is an order of magnitude lower than the well studied oxide polar metals. These materials belong to a broad family of $ABC$ intermetallics adopting the stuffed wurtzite structure, also known as hexagonal Heusler compounds. Scanning transmission electron microscopy (STEM) reveals a polar structure with unidirectionally buckled $BC$ (PtSb, AuGe) planes. Magnetotransport measurements demonstrate good metallic behavior with low residual resistivity ($\rho_{LaAuGe}=59.05$ $\mu\Omega\cdot$cm and $\rho_{LaAPtSb}=27.81$ $\mu\Omega\cdot$cm at 2K) and high carrier density ($n_h\sim 10^{21}$ cm$^{-3}$). Photoemission spectroscopy measurements confirm the band metallicity and are in quantitative agreement with density functional theory (DFT) calculations. Through DFT-Chemical Pressure and Crystal Orbital Hamilton Population analyses, the atomic packing factor is found to support the polar buckling of the structure, though the degree of direct interlayer $B-C$ bonding is limited by repulsion at the $A-C$ contacts. When combined with insulating hexagonal Heuslers, these materials provide a new platform for fully epitaxial, multiferroic heterostructures.
- Published
- 2019
- Full Text
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26. A Narrative Review on the Clinical Utility of Electrical Impedance Spectroscopy for Diagnosing High-Grade Cervical Intraepithelial Neoplasia
- Author
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Panagakis, Georgios P, primary, Machairiotis, Nikolaos, additional, Tsiriva, Maria, additional, Theofanakis, Charalampos, additional, Tsetsa, Paraskevi, additional, Pantelis, Athanasios G, additional, Thomakos, Nikolaos, additional, Rodolakis, Alexandros, additional, and Haidopoulos, Dimitrios, additional
- Published
- 2024
- Full Text
- View/download PDF
27. New boundaries for fertility sparing management in endometrial cancer
- Author
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Rodolakis, Alexandros, Pergialiotis, Vasilis, and Thomakos, Nikolaos
- Published
- 2023
- Full Text
- View/download PDF
28. Quality of life of ovarian cancer patients treated with combined platinum taxane chemotherapy: a systematic review of the literature
- Author
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Pergialiotis, Vasilios, Sotiropoulou, Ioanna Myrto, Liatsou, Efstathia, Liontos, Michalis, Frountzas, Maximos, Thomakos, Nikolaos, Rodolakis, Alexandros, and Haidopoulos, Dimitrios
- Published
- 2022
- Full Text
- View/download PDF
29. Resonant soft x-ray scattering from stripe-ordered La$_{2-x}$Ba$_x$CuO$_4$ detected by a transition edge sensor array detector
- Author
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Joe, Y. I., Fang, Y., Lee, S., Sun, S. X. L., de la Peña, G. A., Doriese, W. B., Morgan, K. M., Fowler, J. W., Vale, L. R., Rodolakis, F., McChesney, J. L., Ullom, J. N., Swetz, D. S., and Abbamonte, P.
- Subjects
Condensed Matter - Strongly Correlated Electrons ,Physics - Instrumentation and Detectors ,Quantum Physics - Abstract
Resonant soft x-ray scattering (RSXS) is a leading probe of valence band order in materials best known for detecting charge density wave order in the copper-oxide superconductors. One of the biggest limitations on the RSXS technique is the presence of a severe fluorescence background which, like the RSXS cross section itself, is enhanced under resonant conditions. This background prevents the study of weak signals such as diffuse scattering from glassy or fluctuating order that is spread widely over momentum space. Recent advances in superconducting transition edge sensor (TES) detectors have led to major improvements in energy resolution and detection efficiency in the soft x-ray range. Here, we perform a RSXS study of stripe-ordered La$_{2-x}$Ba$_x$CuO$_4$ at the Cu $L_{3/2}$ edge (932.2 eV) using a TES detector with 1.5 eV resolution, to evaluate its utility for mitigating the fluorescence background problem. We find that, for suitable degree of detuning from the resonance, the TES rejects the fluorescence background, leading to a 5 to 10 times improvement in the statistical quality of the data compared to an equivalent, energy-integrated measurement. We conclude that a TES presents a promising approach to reducing background in RSXS studies and may lead to new discoveries in materials exhibiting valence band order that is fluctuating or glassy., Comment: 10 pages, 6 figures
- Published
- 2019
- Full Text
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30. Large Fermi Surface Expansion through Anisotropic c-f Mixing in the Semimetallic Kondo Lattice System CeBi
- Author
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Li, Peng, Wu, Zhongzheng, Wu, Fan, Guo, Chunyu, Liu, Yi, Liu, Haijiang, Sun, Zhe, Shi, Ming, Rodolakis, Fanny, McChesney, Jessica L, Cao, Chao, Steglich, Frank, Yuan, Huiqiu, and Liu, Yang
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
Using angle-resolved photoemission spectroscopy (ARPES) and resonant ARPES, we report evidence of strong anisotropic conduction-f electron mixing (c-f mixing) in CeBi by observing a largely expanded Ce-5d pocket at low temperature, with no change in the Bi-6p bands. The Fermi surface (FS) expansion is accompanied by a pronounced spectral weight transfer from the local 4f 0 peak of Ce (corresponding to Ce3+) to the itinerant conduction bands near the Fermi level. Careful analysis suggests that the observed large FS change (with a volume expansion of the electron pocket up to 40%) can most naturally be explained by a small valence change (~ 1%) of Ce, which coexists with a very weak Kondo screening. Our work therefore provides evidence for a FS change driven by real charge fluctuations deep in the Kondo limit, which is made possible by the low carrier density., Comment: 3 figures
- Published
- 2019
- Full Text
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31. High mobility in a van der Waals layered antiferromagnetic metal
- Author
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Lei, Shiming, Lin, Jingjing, Jia, Yanyu, Gray, Mason, Topp, Andreas, Farahi, Gelareh, Klemenz, Sebastian, Gao, Tong, Rodolakis, Fanny, McChesney, Jessica L., Ast, Christian R., Yazdani, Ali, Burch, Kenneth S., Wu, Sanfeng, Ong, N. Phuan, and Schoop, Leslie M.
- Subjects
Condensed Matter - Materials Science - Abstract
Magnetic van der Waals (vdW) materials have been heavily pursued for fundamental physics as well as for device design. Despite the rapid advances, so far magnetic vdW materials are mainly insulating or semiconducting, and none of them possesses a high electronic mobility - a property that is rare in layered vdW materials in general. The realization of a magnetic high-mobility vdW material would open the possibility for novel magnetic twistronic or spintronic devices. Here we report very high carrier mobility in the layered vdW antiferromagnet GdTe3. The electron mobility is beyond 60,000 cm2 V-1 s-1, which is the highest among all known layered magnetic materials, to the best of our knowledge. Among all known vdW materials, the mobility of bulk GdTe3 is comparable to that of black phosphorus, and is only surpassed by graphite. By mechanical exfoliation, we further demonstrate that GdTe3 can be exfoliated to ultrathin flakes of three monolayers, and that the magnetic order and relatively high mobility is retained in approximately 20-nm-thin flakes.
- Published
- 2019
- Full Text
- View/download PDF
32. Electronically enhanced layer buckling and Au-Au dimerization in epitaxial LaAuSb films
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Strohbeen, Patrick J., Du, Dongxue, Zhang, Chenyu, Shourov, Estiaque H., Rodolakis, Fanny, McChesney, Jessica L., Voyles, Paul M., and Kawasaki, Jason K.
- Subjects
Condensed Matter - Materials Science - Abstract
We report the molecular beam epitaxial growth, structure, and electronic measurements of single-crystalline LaAuSb films on Al$_2$O$_3$ (0001) substrates. LaAuSb belongs to a broad family of hexagonal $ABC$ intermetallics in which the magnitude and sign of layer buckling have strong effects on properties, e.g., predicted hyperferroelecticity, polar metallicity, and Weyl and Dirac states. Scanning transmission electron microscopy reveals highly buckled planes of Au-Sb atoms, with strong interlayer Au-Au interactions and a doubling of the unit cell. This buckling is four times larger than the buckling observed in other $ABC$s with similar composition, e.g. LaAuGe and LaPtSb. Photoemission spectroscopy measurements and comparison with theory suggest an electronic driving force for the Au-Au dimerization, since LaAuSb, with a 19-electron count, has one more valence electron per formula unit than most stable $ABC$s. Our results suggest that the electron count, in addition to conventional parameters such as epitaxial strain and chemical pressure, provides a powerful means for tuning the layer buckling in ferroic $ABC$s., Comment: in press
- Published
- 2019
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33. Survival Outcomes of Epithelial Ovarian Cancer Patients Following Dose-dense Versus 3-Weekly Platinum–Paclitaxel Chemotherapy: A Meta-Analysis
- Author
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Pergialiotis, V., Liatsou, E., Thomakos, N., Liontos, M., Frountzas, M., Papapanagiotou, A., Rodolakis, A., and Haidopoulos, D.
- Published
- 2023
- Full Text
- View/download PDF
34. How Bulk Sensitive is Hard X‑ray Photoelectron Spectroscopy: Accounting for the Cathode–Electrolyte Interface when Addressing Oxygen Redox
- Author
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Lebens-Higgins, Zachary W, Chung, Hyeseung, Zuba, Mateusz J, Rana, Jatinkumar, Li, Yixuan, Faenza, Nicholas V, Pereira, Nathalie, McCloskey, Bryan D, Rodolakis, Fanny, Yang, Wanli, Whittingham, M Stanley, Amatucci, Glenn G, Meng, Ying Shirley, Lee, Tien-Lin, and Piper, Louis FJ
- Subjects
Physical Sciences ,Chemical Sciences ,Physical Chemistry ,Chemical sciences ,Physical sciences - Abstract
Sensitivity to the "bulk" oxygen core orbital makes hard X-ray photoelectron spectroscopy (HAXPES) an appealing technique for studying oxygen redox candidates. Various studies have reported an additional O 1s peak (530-531 eV) at high voltages, which has been considered a direct signature of the bulk oxygen redox process. Here, we find the emergence of a 530.4 eV O 1s HAXPES peak for three model cathodes-Li2MnO3, Li-rich NMC, and NMC 442-that shows no clear link to oxygen redox. Instead, the 530.4 eV peak for these three systems is attributed to transition metal reduction and electrolyte decomposition in the near-surface region. Claims of oxygen redox relying on photoelectron spectroscopy must explicitly account for the surface sensitivity of this technique and the extent of the cathode degradation layer.
- Published
- 2020
35. Fermi surface collapse and energy scales in Ce2RhIn8
- Author
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Rodolakis, F., Adriano, C., Restrepo, F., Rosa, P. F. S., Pagliuso, P. G., and Campuzano, J. C.
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
In some metals containing a sub-lattice of rare earth or actinide ions, free local $f$ spins at high temperatures dissolve into the sea of quantum conduction electrons at low temperatures, where they become mobile excitations. Once mobile, the spins acquire charge, forming electrons of heavy mass, known as heavy fermions. In turn, the incorporation of heavy charges into the conduction sea leads to an increase in the volume of the Fermi surface. This process, called Kondo scattering, is accompanied by a dramatic, temperature dependent transformation of the electronic interactions and masses. Since the Kondo phenomena is controlled by quantum fluctuations, here we ask, at which point does the Fermi surface change character? A priori, the answer is not clear, since near its onset, the Kondo effect cannot be described as a simple hybridization of electronic eigenstates. Conventional descriptions of this Kondo scattering process consider that hybridization, Fermi volume change, and $f$-electron mobility occur simultaneously. However, using angle resolved photoemission spectroscopy to measure the evolution of excitations, we find that the changes of the Fermi surface emerge at temperatures an order of magnitude higher than the opening of the hybridization gap, and two orders of magnitude higher than the onset of the coherent character of the $f$-electrons. We suggest that the large changes in Fermi volume, driven by electronic fluctuations, occur at temperatures where the various $\Gamma_x \to \Gamma_y$ crystal field-split $f$ levels become accessible to conduction states of the corresponding symmetries. The separation of these energy scales significantly modifies the conventional description of the Kondo lattice effect, which still lacks a full theoretical description., Comment: Manuscript originally submitted to a peer-reviewed journal on February 27, 2015; please contact corresponding author for more details
- Published
- 2018
36. Cooperative Effects of Strain and Electron Correlation in Epitaxial VO2 and NbO2
- Author
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Lee, Wei-Cheng, Wahila, Matthew J., Mukherjee, Shantanu, Singh, Christopher N., Eustance, Tyler, Regoutz, Anna, Paik, H., Boschker, Jos E., Rodolakis, Fanny, Lee, Tien-Lin, Schlom, D. G., and Piper, Louis F. J.
- Subjects
Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Materials Science - Abstract
We investigate the electronic structure of the epitaxial VO$_2$ films in the rutile phase using the density functional theory combined with the slave spin method (DFT+SS). In DFT-SS, the multiorbital Hubbard interactions are added to a DFT-fit tight-binding model, and we employ the slave-spin method to treat the electron correlation. We find that while stretching the system along the rutile $c$-axis results in a band structure favoring an anisotropic orbital fillings, the electron correlation favors an equal electron filling among $t_{2g}$ orbitals. These two distinct effects cooperatively induce interesting orbital-dependent redistributions of the electron occupations and the spectral weights, which pushes the strained VO$_2$ toward an orbital selective Mott transition (OSMT). The simulated single-particle spectral functions are directly compared to V L-edge resonant X-ray photoemission spectroscopy of epitaxial 10 nm VO$_2$/TiO$_2$ (001) and (100) strain orientations. Excellent agreement is observed between the simulations and experimental data regarding the strain-induced evolution of the lower Hubbard band. Simulations of rutile NbO$_2$ under similar strain conditions as VO$_2$ are performed, and we predict that OSMT will not occur in rutile NbO$_2$. Our results indicates that the electron correlation in VO$_2$ is important and can be modulated even in the rutile phase before the Peierls instability sets in., Comment: 8 pages, 9 figures, invited paper for Special Topic: Strain Engineering in Functional Materials by Journal of Applied Physics
- Published
- 2018
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37. Stabilization of three-dimensional charge order through interplanar orbital hybridization in Pr x Y1−x Ba2Cu3O6+δ
- Author
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Alejandro Ruiz, Brandon Gunn, Yi Lu, Kalyan Sasmal, Camilla M. Moir, Rourav Basak, Hai Huang, Jun-Sik Lee, Fanny Rodolakis, Timothy J. Boyle, Morgan Walker, Yu He, Santiago Blanco-Canosa, Eduardo H. da Silva Neto, M. Brian Maple, and Alex Frano
- Subjects
Science - Abstract
External perturbations can induce 3D charge order in cuprates, but the 3D correlation length is limited and the mechanism is not well understood. Ruiz et al. show that Pr substitution in YBa2Cu3O7 enhances interplanar orbital coupling and stabilizes coherent 3D charge order that coexists with superconductivity.
- Published
- 2022
- Full Text
- View/download PDF
38. Is There a Survival Benefit of Adjuvant Chemotherapy in Stage IC1 Epithelial Ovarian Cancer Patients? A Meta-Analysis
- Author
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Vasilios Pergialiotis, Efstathia Liatsou, Aggeliki Rouvali, Dimitrios Haidopoulos, Dimitrios Efthymios, Michalis Liontos, Alexandros Rodolakis, and Nikolaos Thomakos
- Subjects
ovarian cancer ,cyst rupture ,stage IC1 ,survival ,meta-analysis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
The purpose of the present systematic review is to clarify whether adjuvant chemotherapy improves survival rates in women with stage IC1 ovarian cancer. We searched Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL and Google Scholar. We considered comparative observational studies and randomized trials that investigated survival outcomes (progression-free (PFS) and overall survival (OS)) among women with intraoperative rupture of early-stage epithelial ovarian cancer who received adjuvant chemotherapy and those that did not. Eleven studies, which recruited 7556 patients, were included. The risk of bias was defined as moderate after assessment with the Risk of Bias in non-Randomized Trials tool. Meta-analysis was performed with RStudio. Seven studies investigated the impact of adjuvant chemotherapy on recurrence-free survival of patients experiencing intraoperative cyst rupture for otherwise stage I ovarian cancer. The outcome was not affected by the use of adjuvant chemotherapy as the effect estimate was not significant (HR 1.24, 95% CI 0.74, 2.04). The analysis of data from 5 studies similarly revealed that overall survival rates were comparable among the two groups (HR 0.75, 95% CI 0.54, 1.05). This meta-analysis did not detect any benefit from adjuvant chemotherapy for stage IC ovarian cancer patients with cyst rupture. However, conclusions from this investigation are limited by a study population which included multiple histologic subtypes, high and low grade tumors and incompletely staged patients.
- Published
- 2022
- Full Text
- View/download PDF
39. Neuromorphic learning with Mott insulator NiO
- Author
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Zhang, Zhen, Mondal, Sandip, Mandal, Subhasish, Allred, Jason M., Aghamiri, Neda Alsadat, Fali, Alireza, Zhang, Zhan, Zhou, Hua, Cao, Hui, Rodolakis, Fanny, McChesney, Jessica L., Wang, Qi, Sun, Yifei, Abate, Yohannes, Roy, Kaushik, Rabe, Karin M., and Ramanathan, Shriram
- Published
- 2021
40. Electron doping of NdNiO3 thin films using dual chamber CaH2 annealing
- Author
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Amarasinghe, Dinesh K., Yu, Haoming, Rodolakis, Fanny, Zhou, Hua, Cao, Hui, and Ramanathan, Shriram
- Published
- 2022
- Full Text
- View/download PDF
41. High-resolution full-field structural microscopy of the voltage-induced filament formation in VO2-based neuromorphic devices
- Author
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Kisiel, Elliot, primary, Salev, Pavel, additional, Poudyal, Ishwor, additional, Carneiro, Fellipe, additional, Rodolakis, Fanny, additional, Zhang, Zhan, additional, Shpyrko, Oleg, additional, Schuller, Ivan, additional, Islam, Zahir, additional, and Frano, Alex, additional
- Published
- 2024
- Full Text
- View/download PDF
42. Detection of High-Grade Cervical Intraepithelial Neoplasia by Electrical Impedance Spectroscopy in Women Diagnosed with Low-Grade Cervical Intraepithelial Neoplasia in Cytology
- Author
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Georgios Panagakis, Ioannis K. Papapanagiotou, Charalampos Theofanakis, Paraskevi Tsetsa, Adamantia Kontogeorgi, Nikolaos Thomakos, Alexandros Rodolakis, and Dimitrios Haidopoulos
- Subjects
cervical intraepithelial neoplasia ,colposcopy ,electrical impedance spectroscropy ,high-grade CIN zedscan device ,low-grade CIN ,Science - Abstract
The authors attempt to address the importance of timely detection and management of cervical intraepithelial neoplasia (CIN) to prevent cervical cancer. The study focused on the potential of electrical impedance spectroscopy (EIS) as an adjunct to colposcopy, aiming to enhance the accuracy of identifying high-grade cervical lesions. Colposcopy, a widely used technique, exhibited variable sensitivity in detecting high-grade lesions, which relies on the expertise of the operator. The study’s primary objective is to evaluate the effectiveness of combining colposcopy with EIS in detecting high-grade cervical lesions among patients initially diagnosed with low-grade CIN based on cytology. We employed a cross-sectional observational design, recruiting 101 women with abnormal cervical cytology results. The participants underwent colposcopy with acetic acid and subsequent EIS using the ZedScan device. The ZedScan results are categorized into color-coded probability levels, with red indicating the highest likelihood of high-grade squamous intraepithelial lesions (HSIL) occurrence. Results revealed that ZedScan exhibits a sensitivity rate of 89.5% and a specificity rate of 84% for detecting high-grade lesions. Colposcopy, on the other hand, recorded a sensitivity rate of 85.5% and a specificity rate of 92%. The agreement rate between ZedScan and biopsy is 79.2%, as indicated by a kappa coefficient of 0.71, while the agreement rate between colposcopy and biopsy is 74.3%, with a kappa coefficient of 0.71.
- Published
- 2023
- Full Text
- View/download PDF
43. Functional properties of Yttrium Iron Garnett thin films on graphene-coated Gd3Ga5O12 for remote epitaxial transfer
- Author
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Leontsev, S., Shah, P.J., Kum, H.S., McChesney, J.L., Rodolakis, F.M., van Veenendaal, M., Velez, M., Rao, R., Haskel, D., Kim, J., Reed, A.N., and Page, M.R.
- Published
- 2022
- Full Text
- View/download PDF
44. Surface floating 2D bands in layered nonsymmorphic semimetals: ZrSiS and related compounds
- Author
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Topp, Andreas, Queiroz, Raquel, Grüneis, Andreas, Müchler, Lukas, Rost, Andreas, Varykhalov, Andrei, Marchenko, Dmitry, Krivenkov, Maxim, Rodolakis, Fanny, McChesney, Jessica, Lotsch, Bettina V., Schoop, Leslie M., and Ast, Christian R.
- Subjects
Condensed Matter - Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
In this work, we present a model of the surface states of nonsymmorphic semimetals. These are derived from surface mass terms that lift the high degeneracy imposed in the band structure by the nonsymmorphic bulk symmetries. Reflecting the reduced symmetry at the surface, the bulk bands are strongly modified. This leads to the creation of two-dimensional floating bands, which are distinct from Shockley states, quantum well states or topologically protected surface states. We focus on the layered semimetal ZrSiS to clarify the origin of its surface states. We demonstrate an excellent agreement between DFT calculations and ARPES measurements and present an effective four-band model in which similar surface bands appear. Finally, we emphasize the role of the surface chemical potential by comparing the surface density of states in samples with and without potassium coating. Our findings can be extended to related compounds and generalized to other crystals with nonsymmorphic symmetries., Comment: 8 pages, 5 figures
- Published
- 2017
- Full Text
- View/download PDF
45. Evidence of a second-order Peierls-driven metal-insulator transition in crystalline NbO2
- Author
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Wahila, MJ, Paez, G, Singh, CN, Regoutz, A, Sallis, S, Zuba, MJ, Rana, J, Tellekamp, MB, Boschker, JE, Markurt, T, Swallow, JEN, Jones, LAH, Veal, TD, Yang, W, Lee, TL, Rodolakis, F, Sadowski, JT, Prendergast, D, Lee, WC, Doolittle, WA, and Piper, LFJ
- Abstract
The metal-insulator transition of NbO2 is thought to be important for the functioning of recent niobium oxide-based memristor devices, and is often described as a Mott transition in these contexts. However, the actual transition mechanism remains unclear, as current devices actually employ electroformed NbOx that may be inherently different to crystalline NbO2. We report on our synchrotron x-ray spectroscopy and density-functional-theory study of crystalline, epitaxial NbO2 thin films grown by pulsed laser deposition and molecular beam epitaxy across the metal-insulator transition at ∼810°C. The observed spectral changes reveal a second-order Peierls transition driven by a weakening of Nb dimerization without significant electron correlations, further supported by our density-functional-theory modeling. Our findings indicate that employing crystalline NbO2 as an active layer in memristor devices may facilitate analog control of the resistivity, whereby Joule-heating can modulate Nb-Nb dimer distance and consequently control the opening of a pseudogap.
- Published
- 2019
46. Direct observation of delithiation as the origin of analog memristance in LixNbO2
- Author
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Howard, Sebastian A, Singh, Christopher N, Paez, Galo J, Wahila, Matthew J, Wangoh, Linda W, Sallis, Shawn, Tirpak, Keith, Liang, Yufeng, Prendergast, David, Zuba, Mateusz, Rana, Jatinkumar, Weidenbach, Alex, McCrone, Timothy M, Yang, Wanli, Lee, Tien-Lin, Rodolakis, Fanny, Doolittle, William, Lee, Wei-Cheng, and Piper, Louis FJ
- Subjects
Electrical and Electronic Engineering ,Materials Engineering ,Mechanical Engineering - Abstract
The discovery of analog LixNbO2 memristors revealed a promising new memristive mechanism wherein the diffusion of Li+ rather than O2- ions enables precise control of the resistive states. However, directly correlating lithium concentration with changes to the electronic structure in active layers remains a challenge and is required to truly understand the underlying physics. Chemically delithiated single crystals of LiNbO2 present a model system for correlating lithium variation with spectroscopic signatures from operando soft x-ray spectroscopy studies of device active layers. Using electronic structure modeling of the x-ray spectroscopy of LixNbO2 single crystals, we demonstrate that the intrinsic memristive behavior in LixNbO2 active layers results from field-induced degenerate p-type doping. We show that electrical operation of LixNbO2-based memristors is viable even at marginal Li deficiency and that the analog memristive switching occurs well before the system is fully metallic. This study serves as a benchmark for material synthesis and characterization of future LixNbO2-based memristor devices and suggests that valence change switching is a scalable alternative that circumvents the electroforming typically required for filamentary-based memristors.
- Published
- 2019
47. Chiral structures of electric polarization vectors quantified by X-ray resonant scattering
- Author
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Kook Tae Kim, Margaret R. McCarter, Vladimir A. Stoica, Sujit Das, Christoph Klewe, Elizabeth P. Donoway, David M. Burn, Padraic Shafer, Fanny Rodolakis, Mauro A. P. Gonçalves, Fernando Gómez-Ortiz, Jorge Íñiguez, Pablo García-Fernández, Javier Junquera, Sandhya Susarla, Stephen W. Lovesey, Gerrit van der Laan, Se Young Park, Lane W. Martin, John W. Freeland, Ramamoorthy Ramesh, and Dong Ryeol Lee
- Subjects
Science - Abstract
The polar chiral texture of the vortex or skyrmion structure in ferroelectric oxide PbTiO3/SrTiO3 superlattice attracts attention. Here, the authors report a theoretical framework to probe emergent chirality of electrical polarization textures.
- Published
- 2022
- Full Text
- View/download PDF
48. Persistent Funic Presentation And Sonographic Assesment Of The Risk For Umbilical Cord Prolapse
- Author
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Ioakeim Sapantzoglou, Alexandros Psarris, Panagiota Diamantopoulou, Antonis Koutras, Thomas Ntounis, Savia Pittokopitou, Ioannis Prokopakis, Panagiotis Antsaklis, Marianna Theodora, Michail Sindos, Ekaterini Domali, Alexandros Rodolakis, and Georgios Daskalakis
- Subjects
Medicine ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Published
- 2023
- Full Text
- View/download PDF
49. Caesarean Scar Pregnancy: Single Dose of Intrasac Ultrasound-Guided Methotrexate Injection Seems to be a Safe Option for Treatment
- Author
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Angeliki Rouvalis, Panagiotis Vlastarakos, Georgios Daskalakis, Abraham Pouliakis, Sofoklis Stavrou, Maria Tsiriva, Maria Giourga, Angeliki Gerede, Kalliopi Pappa, Themos Gregoriadis, Dimitrios-Efthymios Vlachos, Alexandros Rodolakis, and Ekaterini Domali
- Subjects
ectopic pregnancy ,cesarean scar pregnancy ,transvaginal ultrasound ,methotrexate ,gynecology ,Medicine ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Published
- 2023
- Full Text
- View/download PDF
50. Subarachnoid hemorrhage in a postpartum mother: A rare manifestation of an uncommon disease
- Author
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Oraianthi Fiste, Evaggelos Mavrothalassitis, Christos Markellos, Alexandros Rodolakis, Flora Zagouri, Meletios-Athanasios Dimopoulos, and Michalis Liontos
- Subjects
Aneurysm ,Subarachnoid hemorrhage ,Choriocarcinoma ,Gestational trophoblastic disease ,Rare gynecological cancers ,Gynecology and obstetrics ,RG1-991 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Subarachnoid hemorrhage, a potentially lethal medical emergency, represents an atypical clinical manifestation of gestational choriocarcinoma. We present the uncommon case of a 31-year-old primigravid female who presented with cerebral oncotic aneurysmal rupture, five weeks after vaginal delivery. Albeit the absence of neurological deficits after endovascular embolization, the patient was soon readmitted, complaining of fever, abdominal pain, and fetid lochia, all suggestive of puerperal endometritis. Upon a comprehensive diagnostic work-up, she was subsequently diagnosed with metastatic choriocarcinoma. Early initiation of multiagent chemotherapy, despite being in septic shock associated with Escherichia coli bacteremia, resulted in favorable prognosis.
- Published
- 2022
- Full Text
- View/download PDF
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