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Hu Y, Ma J, Li Y, Jiang Y, Gawryluk DJ, Hu T, Teyssier J, Multian V, Yin Z, Xu S, Shin S, Plokhikh I, Han X, Plumb NC, Liu Y, Yin JX, Guguchia Z, Zhao Y, Schnyder AP, Wu X, Pomjakushina E, Hasan MZ, Wang N, Shi M. Publisher Correction: Phonon promoted charge density wave in topological kagome metal ScV 6Sn 6. Nat Commun 2024; 15:2196. [PMID: 38467632 PMCID: PMC10928204 DOI: 10.1038/s41467-024-46562-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024] Open
Affiliation(s)
- Yong Hu
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.
- Center of Quantum Materials and Devices and Department of Applied Physics, Chongqing University, 401331, Chongqing, China.
| | - Junzhang Ma
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
- Hong Kong Institute for Advanced Study, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Yinxiang Li
- College of Science, University of Shanghai for Science and Technology, 200093, Shanghai, China
| | - Yuxiao Jiang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, USA
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Tianchen Hu
- International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
| | - Jérémie Teyssier
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211, Geneva 4, Switzerland
| | - Volodymyr Multian
- Advanced Materials Nonlinear Optical Diagnostics lab, Institute of Physics, NAS of Ukraine, 46 Nauky pr., 03028, Kyiv, Ukraine
| | - Zhouyi Yin
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, China
| | - Shuxiang Xu
- International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
| | - Soohyeon Shin
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Igor Plokhikh
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Xinloong Han
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Nicholas C Plumb
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Yang Liu
- Center for Correlated Matter and Department of Physics, Zhejiang University, 310058, Hangzhou, China
| | - Jia-Xin Yin
- Department of physics, Southern University of Science and Technology, 518055, Shenzhen, Guangdong, China
| | - Zurab Guguchia
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Yue Zhao
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, China
| | - Andreas P Schnyder
- Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569, Stuttgart, Germany
| | - Xianxin Wu
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, USA
| | - Nanlin Wang
- International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100913, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100871, China
| | - Ming Shi
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.
- Center for Correlated Matter and Department of Physics, Zhejiang University, 310058, Hangzhou, China.
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2
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Hu Y, Ma J, Li Y, Jiang Y, Gawryluk DJ, Hu T, Teyssier J, Multian V, Yin Z, Xu S, Shin S, Plokhikh I, Han X, Plumb NC, Liu Y, Yin JX, Guguchia Z, Zhao Y, Schnyder AP, Wu X, Pomjakushina E, Hasan MZ, Wang N, Shi M. Phonon promoted charge density wave in topological kagome metal ScV 6Sn 6. Nat Commun 2024; 15:1658. [PMID: 38395887 PMCID: PMC10891150 DOI: 10.1038/s41467-024-45859-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV6Sn6, a bilayer kagome metal featuring an intriguing [Formula: see text] CDW order, offers a novel platform to explore the underlying mechanism behind the unconventional CDW. Here, we combine high-resolution angle-resolved photoemission spectroscopy, Raman scattering and density functional theory to investigate the electronic structure and phonon modes of ScV6Sn6. We identify topologically nontrivial surface states and multiple van Hove singularities (VHSs) in the vicinity of the Fermi level, with one VHS aligning with the in-plane component of the CDW vector near the [Formula: see text] point. Additionally, Raman measurements indicate a strong electron-phonon coupling, as evidenced by a two-phonon mode and new emergent modes. Our findings highlight the fundamental role of lattice degrees of freedom in promoting the CDW in ScV6Sn6.
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Affiliation(s)
- Yong Hu
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.
- Center of Quantum Materials and Devices and Department of Applied Physics, Chongqing University, 401331, Chongqing, China.
| | - Junzhang Ma
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
- Hong Kong Institute for Advanced Study, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Yinxiang Li
- College of Science, University of Shanghai for Science and Technology, 200093, Shanghai, China
| | - Yuxiao Jiang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, USA
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Tianchen Hu
- International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
| | - Jérémie Teyssier
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211, Geneva 4, Switzerland
| | - Volodymyr Multian
- Advanced Materials Nonlinear Optical Diagnostics lab, Institute of Physics, NAS of Ukraine, 46 Nauky pr., 03028, Kyiv, Ukraine
| | - Zhouyi Yin
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, China
| | - Shuxiang Xu
- International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
| | - Soohyeon Shin
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Igor Plokhikh
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Xinloong Han
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Nicholas C Plumb
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Yang Liu
- Center for Correlated Matter and Department of Physics, Zhejiang University, 310058, Hangzhou, China
| | - Jia-Xin Yin
- Department of physics, Southern University of Science and Technology, 518055, Shenzhen, Guangdong, China
| | - Zurab Guguchia
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Yue Zhao
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, China
| | - Andreas P Schnyder
- Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569, Stuttgart, Germany
| | - Xianxin Wu
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, USA
| | - Nanlin Wang
- International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100913, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100871, China
| | - Ming Shi
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.
- Center for Correlated Matter and Department of Physics, Zhejiang University, 310058, Hangzhou, China.
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3
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Marelli E, Lyu J, Morin M, Leménager M, Shang T, Yüzbasi NS, Aegerter D, Huang J, Daffé ND, Clark AH, Sheptyakov D, Graule T, Nachtegaal M, Pomjakushina E, Schmidt TJ, Krack M, Fabbri E, Medarde M. Cobalt-free layered perovskites RBaCuFeO 5+δ (R = 4f lanthanide) as electrocatalysts for the oxygen evolution reaction. EES Catal 2024; 2:335-350. [PMID: 38222064 PMCID: PMC10782807 DOI: 10.1039/d3ey00142c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 10/30/2023] [Indexed: 01/16/2024]
Abstract
Co-based perovskite oxides are intensively studied as promising catalysts for electrochemical water splitting in an alkaline environment. However, the increasing Co demand by the battery industry is pushing the search for Co-free alternatives. Here we report a systematic study of the Co-free layered perovskite family RBaCuFeO5+δ (R = 4f lanthanide), where we uncover the existence of clear correlations between electrochemical properties and several physicochemical descriptors. Using a combination of advanced neutron and X-ray synchrotron techniques with ab initio DFT calculations we demonstrate and rationalize the positive impact of a large R ionic radius in their oxygen evolution reaction (OER) activity. We also reveal that, in these materials, Fe3+ is the transition metal cation the most prone to donate electrons. We also show that similar R3+/Ba2+ ionic radii favor the incorporation and mobility of oxygen in the layered perovskite structure and increase the number of available O diffusion paths, which have an additional, positive impact on both, the electric conductivity and the OER process. An unexpected result is the observation of a clear surface reconstruction exclusively in oxygen-rich samples (δ > 0), a fact that could be related to their superior OER activity. The encouraging intrinsic OER values obtained for the most active electrocatalyst (LaBaCuFeO5.49), together with the possibility of industrially producing this material in nanocrystalline form should inspire the design of other Co-free oxide catalysts with optimal properties for electrochemical water splitting.
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Affiliation(s)
- Elena Marelli
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
- Electrochemistry Laboratory, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Jike Lyu
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Mickaël Morin
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
- Excelsus Structural Solutions (Swiss) AG, PARK InnovAARE CH-5234 Villigen PSI Switzerland
| | - Maxime Leménager
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Tian Shang
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University Shanghai China
| | - N Sena Yüzbasi
- High Performance Ceramics, EMPA, Swiss Federal Laboratories for Materials Science and Technology CH-8600 Dübendorf Switzerland
| | - Dino Aegerter
- Electrochemistry Laboratory, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Jinzhen Huang
- Electrochemistry Laboratory, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Niéli D Daffé
- Laboratory for Condensed Matter, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Adam H Clark
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Denis Sheptyakov
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Thomas Graule
- High Performance Ceramics, EMPA, Swiss Federal Laboratories for Materials Science and Technology CH-8600 Dübendorf Switzerland
| | - Maarten Nachtegaal
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Thomas J Schmidt
- Electrochemistry Laboratory, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
- Laboratory of Physical Chemistry, ETH Zürich CH-8093 Zürich Switzerland
| | - Matthias Krack
- Laboratory for Materials Simulations, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Emiliana Fabbri
- Electrochemistry Laboratory, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
| | - Marisa Medarde
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland
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4
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Fogh E, Nayak M, Prokhnenko O, Bartkowiak M, Munakata K, Soh JR, Turrini AA, Zayed ME, Pomjakushina E, Kageyama H, Nojiri H, Kakurai K, Normand B, Mila F, Rønnow HM. Field-induced bound-state condensation and spin-nematic phase in SrCu 2(BO 3) 2 revealed by neutron scattering up to 25.9 T. Nat Commun 2024; 15:442. [PMID: 38200029 PMCID: PMC10781965 DOI: 10.1038/s41467-023-44115-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 11/30/2023] [Indexed: 01/12/2024] Open
Abstract
In quantum magnetic materials, ordered phases induced by an applied magnetic field can be described as the Bose-Einstein condensation (BEC) of magnon excitations. In the strongly frustrated system SrCu2(BO3)2, no clear magnon BEC could be observed, pointing to an alternative mechanism, but the high fields required to probe this physics have remained a barrier to detailed investigation. Here we exploit the first purpose-built high-field neutron scattering facility to measure the spin excitations of SrCu2(BO3)2 up to 25.9 T and use cylinder matrix-product-states (MPS) calculations to reproduce the experimental spectra with high accuracy. Multiple unconventional features point to a condensation of S = 2 bound states into a spin-nematic phase, including the gradients of the one-magnon branches and the persistence of a one-magnon spin gap. This gap reflects a direct analogy with superconductivity, suggesting that the spin-nematic phase in SrCu2(BO3)2 is best understood as a condensate of bosonic Cooper pairs.
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Affiliation(s)
- Ellen Fogh
- Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
| | - Mithilesh Nayak
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
| | | | - Maciej Bartkowiak
- Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109, Berlin, Germany
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Harwell, OX11 0QX, UK
| | - Koji Munakata
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai, Ibaraki, 319-1106, Japan
| | - Jian-Rui Soh
- Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Alexandra A Turrini
- Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232, Villigen-PSI, Switzerland
| | - Mohamed E Zayed
- Department of Physics, Carnegie Mellon University in Qatar, Education City, PO Box 24866, Doha, Qatar
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Hiroshi Kageyama
- Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Hiroyuki Nojiri
- Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japan
| | - Kazuhisa Kakurai
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai, Ibaraki, 319-1106, Japan
| | - Bruce Normand
- Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
- Laboratory for Theoretical and Computational Physics, Paul Scherrer Institute, CH-5232, Villigen-PSI, Switzerland
| | - Frédéric Mila
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Henrik M Rønnow
- Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
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5
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Singh D, Fujishiro Y, Hayami S, Moody SH, Nomoto T, Baral PR, Ukleev V, Cubitt R, Steinke NJ, Gawryluk DJ, Pomjakushina E, Ōnuki Y, Arita R, Tokura Y, Kanazawa N, White JS. Transition between distinct hybrid skyrmion textures through their hexagonal-to-square crystal transformation in a polar magnet. Nat Commun 2023; 14:8050. [PMID: 38052859 DOI: 10.1038/s41467-023-43814-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 11/21/2023] [Indexed: 12/07/2023] Open
Abstract
Magnetic skyrmions, topological vortex-like spin textures, garner significant interest due to their unique properties and potential applications in nanotechnology. While they typically form a hexagonal crystal with distinct internal magnetisation textures known as Bloch- or Néel-type, recent theories suggest the possibility for direct transitions between skyrmion crystals of different lattice structures and internal textures. To date however, experimental evidence for these potentially useful phenomena have remained scarce. Here, we discover the polar tetragonal magnet EuNiGe3 to host two hybrid skyrmion phases, each with distinct internal textures characterised by anisotropic combinations of Bloch- and Néel-type windings. Variation of the magnetic field drives a direct transition between the two phases, with the modification of the hybrid texture concomitant with a hexagonal-to-square skyrmion crystal transformation. We explain these observations with a theory that includes the key ingredients of momentum-resolved Ruderman-Kittel-Kasuya-Yosida and Dzyaloshinskii-Moriya interactions that compete at the observed low symmetry magnetic skyrmion crystal wavevectors. Our findings underscore the potential of polar magnets with rich interaction schemes as promising for discovering new topological magnetic phases.
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Affiliation(s)
- Deepak Singh
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232, Villigen, Switzerland.
| | - Yukako Fujishiro
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan
| | - Satoru Hayami
- Graduate School of Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Samuel H Moody
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232, Villigen, Switzerland
| | - Takuya Nomoto
- Research Center for Advanced Science and Technology, University of Tokyo, Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Priya R Baral
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232, Villigen, Switzerland
| | - Victor Ukleev
- Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109, Berlin, Germany
| | - Robert Cubitt
- Institut-Laue-Langevin, 6 rue Jules Horowitz, Grenoble, 38000, France
| | | | - Dariusz J Gawryluk
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institut (PSI), CH-5232, Villigen PSI, Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institut (PSI), CH-5232, Villigen PSI, Switzerland
| | - Yoshichika Ōnuki
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan
| | - Ryotaro Arita
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan
- Research Center for Advanced Science and Technology, University of Tokyo, Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Yoshinori Tokura
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan
- Department of Applied Physics, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan
| | - Naoya Kanazawa
- Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, 153-8505, Japan
| | - Jonathan S White
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232, Villigen, Switzerland.
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6
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Guguchia Z, Gawryluk DJ, Shin S, Hao Z, Mielke Iii C, Das D, Plokhikh I, Liborio L, Shenton JK, Hu Y, Sazgari V, Medarde M, Deng H, Cai Y, Chen C, Jiang Y, Amato A, Shi M, Hasan MZ, Yin JX, Khasanov R, Pomjakushina E, Luetkens H. Hidden magnetism uncovered in a charge ordered bilayer kagome material ScV 6Sn 6. Nat Commun 2023; 14:7796. [PMID: 38016982 PMCID: PMC10684576 DOI: 10.1038/s41467-023-43503-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 11/10/2023] [Indexed: 11/30/2023] Open
Abstract
Charge ordered kagome lattices have been demonstrated to be intriguing platforms for studying the intertwining of topology, correlation, and magnetism. The recently discovered charge ordered kagome material ScV6Sn6 does not feature a magnetic groundstate or excitations, thus it is often regarded as a conventional paramagnet. Here, using advanced muon-spin rotation spectroscopy, we uncover an unexpected hidden magnetism of the charge order. We observe an enhancement of the internal field width sensed by the muon ensemble, which takes place within the charge ordered state. More importantly, the muon spin relaxation rate below the charge ordering temperature is substantially enhanced by applying an external magnetic field. Taken together with the hidden magnetism found in AV3Sb5 (A = K, Rb, Cs) and FeGe kagome systems, our results suggest ubiqitous time-reversal symmetry-breaking in charge ordered kagome lattices.
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Affiliation(s)
- Z Guguchia
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland.
| | - D J Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.
| | - S Shin
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - Z Hao
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - C Mielke Iii
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - D Das
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - I Plokhikh
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - L Liborio
- Scientific Computing Department, Science & Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - J Kane Shenton
- Scientific Computing Department, Science & Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - Y Hu
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - V Sazgari
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - M Medarde
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - H Deng
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Y Cai
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - C Chen
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Y Jiang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - A Amato
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - M Shi
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - M Z Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
- Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, NJ, 08540, USA
- Quantum Science Center, Oak Ridge, TN, 37831, USA
| | - J-X Yin
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - R Khasanov
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - E Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - H Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
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7
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Tam DW, Colonna N, Kumar N, Piamonteze C, Alarab F, Strocov VN, Cervellino A, Fennell T, Gawryluk DJ, Pomjakushina E, Soh Y, Kenzelmann M. Charge fluctuations in the intermediate-valence ground state of SmCoIn 5. Commun Phys 2023; 6:223. [PMID: 38665398 PMCID: PMC11041663 DOI: 10.1038/s42005-023-01339-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 08/08/2023] [Indexed: 04/28/2024]
Abstract
The microscopic mechanism of heavy band formation, relevant for unconventional superconductivity in CeCoIn5 and other Ce-based heavy fermion materials, depends strongly on the efficiency with which f electrons are delocalized from the rare earth sites and participate in a Kondo lattice. Replacing Ce3+ (4f1, J = 5/2) with Sm3+ (4f5, J = 5/2), we show that a combination of the crystal electric field and on-site Coulomb repulsion causes SmCoIn5 to exhibit a Γ7 ground state similar to CeCoIn5 with multiple f electrons. We show that with this single-ion ground state, SmCoIn5 exhibits a temperature-induced valence crossover consistent with a Kondo scenario, leading to increased delocalization of f holes below a temperature scale set by the crystal field, Tv ≈ 60 K. Our result provides evidence that in the case of many f electrons, the crystal field remains the dominant tuning knob in controlling the efficiency of delocalization near a heavy fermion quantum critical point, and additionally clarifies that charge fluctuations play a general role in the ground state of "115" materials.
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Affiliation(s)
- David W. Tam
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Nicola Colonna
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen, Switzerland
- National Centre for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Neeraj Kumar
- Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Cinthia Piamonteze
- Photon Science Division, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Fatima Alarab
- Photon Science Division, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | | | - Antonio Cervellino
- Photon Science Division, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Tom Fennell
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Y. Soh
- Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Michel Kenzelmann
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen, Switzerland
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8
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Adamus P, Xu B, Marsik P, Dubroka A, Barabasová P, Růžičková H, Puphal P, Pomjakushina E, Tallon JL, Mathis YL, Munzar D, Bernhard C. Analogies of phonon anomalies and electronic gap features in the infrared response of Sr14-xCa xCu 24O 41and underdoped YBa 2Cu 3O6+x. Rep Prog Phys 2023; 86:044502. [PMID: 36821858 DOI: 10.1088/1361-6633/acbe4f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
We present an experimental and theoretical study which compares the phonon anomalies and the electronic gap features in the infrared response of the weakly coupled two-leg-ladders in Sr14-xCaxCu24O41(SCCO) with those of the underdoped high-Tcsuperconductor YBa2Cu3O6+x(YBCO) and thereby reveals some surprising analogies. Specifically, we present a phenomenological model that describes the anomalous doping- and temperature-dependence of some of the phonon features in thea-axis response (field along the rungs of the ladders) of SCCO. It assumes that the phonons are coupled to charge oscillations within the ladders. Their changes with decreasing temperature reveal the formation of a crystal (density wave) of hole pairs that are oriented along the rungs. We also discuss the analogy to a similar model that was previously used to explain the phonon anomalies and an electronic plasma mode in thec-axis response (field perpendicular to the CuO2planes) of YBCO. We further confirm that an insulator-like pseudogap develops in thea-axis conductivity of SCCO which closely resembles that in thec-axis conductivity of YBCO. Most surprisingly, we find that thec-axis conductivity (field along the legs of the ladders) of SCCO is strikingly similar to the in-plane one (field parallel to the CuO2planes) of YBCO. Notably, in both cases a dip feature develops in the normal state spectra that is connected with a spectral weight shift toward low frequencies and can thus be associated with precursor superconducting pairing correlations that are lacking macroscopic phase coherence. This SCCO-YBCO analogy indicates that collective degrees of freedom contribute to the low-energy response of underdoped highTccuprates and it even suggests that the charges in the CuO2planes tend to segregate forming quasi-one-dimensional structures similar to the two-leg ladders, as predicted for the stripe-scenario or certain intertwinned states.
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Affiliation(s)
- Petr Adamus
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Bing Xu
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Premysl Marsik
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - Adam Dubroka
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Paulína Barabasová
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Hana Růžičková
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Pascal Puphal
- Laboratory for Multiscale Materials Experiments, PSI, 5232 Villigen, Switzerland
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | | | - Jeffery L Tallon
- Victoria University of Wellington, Robinson Research Institute, POB 33436, Lower Hutt 5046, New Zealand
| | - Yves-Laurent Mathis
- Karlsruhe Institute of Technology, Institute for Beam Physics and Technology, Hermann-von-Helmhotz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Dominik Munzar
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Christian Bernhard
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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9
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von Arx K, Wang Q, Mustafi S, Mazzone DG, Horio M, Mukkattukavil DJ, Pomjakushina E, Pyon S, Takayama T, Takagi H, Kurosawa T, Momono N, Oda M, Brookes NB, Betto D, Zhang W, Asmara TC, Tseng Y, Schmitt T, Sassa Y, Chang J. Fate of charge order in overdoped La-based cuprates. NPJ Quantum Mater 2023; 8:7. [PMID: 38666240 PMCID: PMC11041719 DOI: 10.1038/s41535-023-00539-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 01/09/2023] [Indexed: 04/28/2024]
Abstract
In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in La2-xSrxCuO4 and La1.8-xEu0.2SrxCuO4. Ultra high energy resolution experiments demonstrate the importance of the separation of inelastic and elastic scattering processes. Long-range temperature-dependent stripe order is only found below optimal doping. At higher doping, short-range temperature-independent correlations are present up to the highest doping measured. This transformation is distinct from and preempts the pseudogap critical doping. We argue that the doping and temperature-independent short-range correlations originate from unresolved electron-phonon coupling that broadly peaks at the stripe ordering vector. In La2-xSrxCuO4, long-range static stripe order vanishes around optimal doping and we discuss both quantum critical and crossover scenarios.
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Affiliation(s)
- K. von Arx
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
- Department of Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Qisi Wang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - S. Mustafi
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - D. G. Mazzone
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen, PSI Switzerland
| | - M. Horio
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581 Japan
| | - D. John Mukkattukavil
- Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden
| | | | - S. Pyon
- Department of Applied Physics, The University of Tokyo, Tokyo, 113-8646 Japan
| | - T. Takayama
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
| | - H. Takagi
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
- Department of Physics, The University of Tokyo, Tokyo, 113-0033 Japan
| | - T. Kurosawa
- Department of Physics, Hokkaido University, Sapporo, 060-0810 Japan
| | - N. Momono
- Department of Physics, Hokkaido University, Sapporo, 060-0810 Japan
- Department of Applied Sciences, Muroran Institute of Technology, Muroran, 050-8585 Japan
| | - M. Oda
- Department of Physics, Hokkaido University, Sapporo, 060-0810 Japan
| | - N. B. Brookes
- European Synchrotron Radiation Facility, B.P. 220, 38043 Grenoble, France
| | - D. Betto
- European Synchrotron Radiation Facility, B.P. 220, 38043 Grenoble, France
| | - W. Zhang
- Swiss Light Source, Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, PSI Switzerland
| | - T. C. Asmara
- Swiss Light Source, Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, PSI Switzerland
| | - Y. Tseng
- Swiss Light Source, Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, PSI Switzerland
| | - T. Schmitt
- Swiss Light Source, Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, PSI Switzerland
| | - Y. Sassa
- Department of Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - J. Chang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
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10
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Shang T, Zhao J, Hu LH, Ma J, Gawryluk DJ, Zhu X, Zhang H, Zhen Z, Yu B, Xu Y, Zhan Q, Pomjakushina E, Shi M, Shiroka T. Unconventional superconductivity in topological Kramers nodal-line semimetals. Sci Adv 2022; 8:eabq6589. [PMID: 36306356 PMCID: PMC9616505 DOI: 10.1126/sciadv.abq6589] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Crystalline symmetry is a defining factor of the electronic band topology in solids, where many-body interactions often induce a spontaneous breaking of symmetry. Superconductors lacking an inversion center are among the best systems to study such effects or even to achieve topological superconductivity. Here, we demonstrate that TRuSi materials (with T a transition metal) belong to this class. Their bulk normal states behave as three-dimensional Kramers nodal-line semimetals, characterized by large antisymmetric spin-orbit couplings and by hourglass-like dispersions. Our muon-spin spectroscopy measurements show that certain TRuSi compounds spontaneously break the time-reversal symmetry at the superconducting transition, while unexpectedly showing a fully gapped superconductivity. Their unconventional behavior is consistent with a unitary (s + ip) pairing, reflecting a mixture of spin singlets and spin triplets. By combining an intrinsic time-reversal symmetry-breaking superconductivity with nontrivial electronic bands, TRuSi compounds provide an ideal platform for investigating the rich interplay between unconventional superconductivity and the exotic properties of Kramers nodal-line/hourglass fermions.
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Affiliation(s)
- Tian Shang
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Jianzhou Zhao
- Co-Innovation Center for New Energetic Materials, Southwest University of Science and Technology, Mianyang 621010, China
| | - Lun-Hui Hu
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA
| | - Junzhang Ma
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Xiaoyan Zhu
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Hui Zhang
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Zhixuan Zhen
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Bocheng Yu
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Yang Xu
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Qingfan Zhan
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Ming Shi
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Toni Shiroka
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zürich, Switzerland
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11
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Plokhikh I, Pomjakushin V, Gawryluk DJ, Zaharko O, Pomjakushina E. Competing Magnetic Phases in LnSbTe ( Ln = Ho and Tb). Inorg Chem 2022; 61:11399-11409. [PMID: 35797720 DOI: 10.1021/acs.inorgchem.2c01711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The interplay between a topological electronic structure and magnetism may result in intricate physics. In this work, we describe a case of rather peculiar coexistence or competition of several magnetic phases below seemingly single antiferromagnetic transition in LnSbTe (Ln = Ho and Tb) topological semimetals, the magnetic members of the ZrSiS/PbFCl structure type (space group P4/nmm). Neutron diffraction experiments reveal a complex multi-step order below TN = 3.8 K (Ln = Ho) and TN = 6.4 K (Ln = Tb). Magnetic phases can be described using four propagation vectors k1 = (1/2 0 0) and k2 = (1/2 0 1/4) at a base temperature of 1.7 K, which transform into incommensurate vectors k1' = (1/2 - δ 0 0) and k3 = (1/2 - δ 0 1/2) at elevated temperatures in both compounds. Together with the refined models of magnetic structures, we present the group theoretical analysis of magnetic symmetry of the proposed solutions. These results prompt further investigations of the relation between the electronic structure of those semimetals and the determined antiferromagnetic ordering existing therein.
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Affiliation(s)
- Igor Plokhikh
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, PSI, Villigen CH-5232, Switzerland
| | - Vladimir Pomjakushin
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut, PSI, Villigen CH-5232, Switzerland
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, PSI, Villigen CH-5232, Switzerland
| | - Oksana Zaharko
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut, PSI, Villigen CH-5232, Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, PSI, Villigen CH-5232, Switzerland
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12
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Zhang H, Zhu XY, Xu Y, Gawryluk DJ, Xie W, Ju SL, Shi M, Shiroka T, Zhan QF, Pomjakushina E, Shang T. Giant magnetoresistance and topological Hall effect in the EuGa 4antiferromagnet. J Phys Condens Matter 2021; 34:034005. [PMID: 34666329 DOI: 10.1088/1361-648x/ac3102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 10/19/2021] [Indexed: 06/13/2023]
Abstract
We report on systematic temperature- and magnetic field-dependent studies of the EuGa4binary compound, which crystallizes in a centrosymmetric tetragonal BaAl4-type structure with space groupI4/mmm. The electronic properties of EuGa4single crystals, with an antiferromagnetic (AFM) transition atTN∼ 16.4 K, were characterized via electrical resistivity and magnetization measurements. A giant nonsaturating magnetoresistance was observed at low temperatures, reaching∼7×104% at 2 K in a magnetic field of 9 T. In the AFM state, EuGa4undergoes a series of metamagnetic transitions in an applied magnetic field, clearly manifested in its field-dependent electrical resistivity. BelowTN, in the ∼4-7 T field range, we observe also a clear hump-like anomaly in the Hall resistivity which is part of the anomalous Hall resistivity. We attribute such a hump-like feature to the topological Hall effect, usually occurring in noncentrosymmetric materials known to host topological spin textures (as e.g., magnetic skyrmions). Therefore, the family of materials with a tetragonal BaAl4-type structure, to which EuGa4and EuAl4belong, seems to comprise suitable candidates on which one can study the interplay among correlated-electron phenomena (such as charge-density wave or exotic magnetism) with topological spin textures and topologically nontrivial bands.
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Affiliation(s)
- H Zhang
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, People's Republic of China
| | - X Y Zhu
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, People's Republic of China
| | - Y Xu
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, People's Republic of China
| | - D J Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - W Xie
- DESY, Notkestraβe 85, D-22607 Hamburg, Germany
| | - S L Ju
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Shi
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - T Shiroka
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zurich, Switzerland
| | - Q F Zhan
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, People's Republic of China
| | | | - T Shang
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, People's Republic of China
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13
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Marelli E, Gazquez J, Poghosyan E, Müller E, Gawryluk DJ, Pomjakushina E, Sheptyakov D, Piamonteze C, Aegerter D, Schmidt TJ, Medarde M, Fabbri E. Correlation between Oxygen Vacancies and Oxygen Evolution Reaction Activity for a Model Electrode: PrBaCo
2
O
5+
δ
. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Elena Marelli
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | - Jaume Gazquez
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) Campus UAB, Bellaterra 08193 Barcelona Spain
| | - Emiliya Poghosyan
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | - Elisabeth Müller
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | | | | | - Denis Sheptyakov
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | - Cinthia Piamonteze
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | - Dino Aegerter
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | - Thomas J. Schmidt
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
- Laboratory of Physical Chemistry ETH Zurich 8093 Zurich Switzerland
| | - Marisa Medarde
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
| | - Emiliana Fabbri
- Paul Scherrer Institute Forschungsstrasse 111 5232 Villigen PSI Switzerland
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14
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Marelli E, Gazquez J, Poghosyan E, Müller E, Gawryluk DJ, Pomjakushina E, Sheptyakov D, Piamonteze C, Aegerter D, Schmidt TJ, Medarde M, Fabbri E. Correlation between Oxygen Vacancies and Oxygen Evolution Reaction Activity for a Model Electrode: PrBaCo 2 O 5+δ. Angew Chem Int Ed Engl 2021; 60:14609-14619. [PMID: 33826206 DOI: 10.1002/anie.202103151] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Indexed: 11/12/2022]
Abstract
The role of the perovskite lattice oxygen in the oxygen evolution reaction (OER) is systematically studied in the PrBaCo2 O5+δ family. The reduced number of physical/chemical variables combined with in-depth characterizations such as neutron dif-fraction, O K-edge X-ray absorption spectroscopy (XAS), electron energy loss spectroscopy (EELS), magnetization and scanning transmission electron microscopy (STEM) studies, helps investigating the complex correlation between OER activity and a single perovskite property, such as the oxygen content. Larger amount of oxygen vacancies appears to facilitate the OER, possibly contributing to the mechanism involving the oxidation of lattice oxygen, i.e., the lattice oxygen evolution reaction (LOER). Furthermore, not only the number of vacancies but also their local arrangement in the perovskite lattice influences the OER activity, with a clear drop for the more stable, ordered stoichiometry.
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Affiliation(s)
- Elena Marelli
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Jaume Gazquez
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, Bellaterra, 08193, Barcelona, Spain
| | - Emiliya Poghosyan
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Elisabeth Müller
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Dariusz J Gawryluk
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | | | - Denis Sheptyakov
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Cinthia Piamonteze
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Dino Aegerter
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Thomas J Schmidt
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland.,Laboratory of Physical Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Marisa Medarde
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Emiliana Fabbri
- Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
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15
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Jiménez JL, Crone SPG, Fogh E, Zayed ME, Lortz R, Pomjakushina E, Conder K, Läuchli AM, Weber L, Wessel S, Honecker A, Normand B, Rüegg C, Corboz P, Rønnow HM, Mila F. A quantum magnetic analogue to the critical point of water. Nature 2021; 592:370-375. [PMID: 33854247 DOI: 10.1038/s41586-021-03411-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 02/26/2021] [Indexed: 02/02/2023]
Abstract
At the liquid-gas phase transition in water, the density has a discontinuity at atmospheric pressure; however, the line of these first-order transitions defined by increasing the applied pressure terminates at the critical point1, a concept ubiquitous in statistical thermodynamics2. In correlated quantum materials, it was predicted3 and then confirmed experimentally4,5 that a critical point terminates the line of Mott metal-insulator transitions, which are also first-order with a discontinuous charge carrier density. In quantum spin systems, continuous quantum phase transitions6 have been controlled by pressure7,8, applied magnetic field9,10 and disorder11, but discontinuous quantum phase transitions have received less attention. The geometrically frustrated quantum antiferromagnet SrCu2(BO3)2 constitutes a near-exact realization of the paradigmatic Shastry-Sutherland model12-14 and displays exotic phenomena including magnetization plateaus15, low-lying bound-state excitations16, anomalous thermodynamics17 and discontinuous quantum phase transitions18,19. Here we control both the pressure and the magnetic field applied to SrCu2(BO3)2 to provide evidence of critical-point physics in a pure spin system. We use high-precision specific-heat measurements to demonstrate that, as in water, the pressure-temperature phase diagram has a first-order transition line that separates phases with different local magnetic energy densities, and that terminates at an Ising critical point. We provide a quantitative explanation of our data using recently developed finite-temperature tensor-network methods17,20-22. These results further our understanding of first-order quantum phase transitions in quantum magnetism, with potential applications in materials where anisotropic spin interactions produce the topological properties23,24 that are useful for spintronic applications.
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Affiliation(s)
- J Larrea Jiménez
- Laboratory for Quantum Matter under Extreme Conditions, Institute of Physics, University of São Paulo, São Paulo, Brazil.,Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - S P G Crone
- Institute for Theoretical Physics, University of Amsterdam, Amsterdam, The Netherlands.,Delta Institute for Theoretical Physics, University of Amsterdam, Amsterdam, The Netherlands
| | - E Fogh
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - M E Zayed
- Department of Physics, Carnegie Mellon University in Qatar, Doha, Qatar
| | - R Lortz
- Department of Physics, Hong Kong University of Science and Technology, Kowloon, Hong Kong
| | - E Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - K Conder
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - A M Läuchli
- Institut für Theoretische Physik, Universität Innsbruck, Innsbruck, Austria
| | - L Weber
- Institut für Theoretische Festkörperphysik, RWTH Aachen University, Aachen, Germany
| | - S Wessel
- Institut für Theoretische Festkörperphysik, RWTH Aachen University, Aachen, Germany
| | - A Honecker
- Laboratoire de Physique Théorique et Modélisation, CNRS UMR 8089, CY Cergy Paris Université, Cergy-Pontoise, France
| | - B Normand
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.,Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Ch Rüegg
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.,Paul Scherrer Institute, Villigen-PSI, Switzerland.,Institute for Quantum Electronics, ETH Zürich, Hönggerberg, Switzerland.,Department of Quantum Matter Physics, University of Geneva, Geneva, Switzerland
| | - P Corboz
- Institute for Theoretical Physics, University of Amsterdam, Amsterdam, The Netherlands.,Delta Institute for Theoretical Physics, University of Amsterdam, Amsterdam, The Netherlands
| | - H M Rønnow
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | - F Mila
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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16
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Cho CW, Shen J, Lyu J, Atanov O, Chen Q, Lee SH, Hor YS, Gawryluk DJ, Pomjakushina E, Bartkowiak M, Hecker M, Schmalian J, Lortz R. Z 3-vestigial nematic order due to superconducting fluctuations in the doped topological insulators Nb xBi 2Se 3 and Cu xBi 2Se 3. Nat Commun 2020; 11:3056. [PMID: 32546839 PMCID: PMC7298044 DOI: 10.1038/s41467-020-16871-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 05/29/2020] [Indexed: 12/04/2022] Open
Abstract
A state of matter with a multi-component order parameter can give rise to vestigial order. In the vestigial phase, the primary order is only partially melted, leaving a remaining symmetry breaking behind, an effect driven by strong classical or quantum fluctuations. Vestigial states due to primary spin and charge-density-wave order have been discussed in iron-based and cuprate materials. Here we present the observation of a partially melted superconductivity in which pairing fluctuations condense at a separate phase transition and form a nematic state with broken Z3, i.e., three-state Potts-model symmetry. Thermal expansion, specific heat and magnetization measurements of the doped topological insulators NbxBi2Se3 and CuxBi2Se3 reveal that this symmetry breaking occurs at [Formula: see text] above [Formula: see text], along with an onset of superconducting fluctuations. Thus, before Cooper pairs establish long-range coherence at Tc, they fluctuate in a way that breaks the rotational invariance at Tnem and induces a crystalline distortion.
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Affiliation(s)
- Chang-Woo Cho
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Junying Shen
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
- Laboratory for Neutron and Muon Instrumentation, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Jian Lyu
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Omargeldi Atanov
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Qianxue Chen
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Seng Huat Lee
- Department of Physics, Missouri University of Science and Technology, Rolla, MO, 65409, USA
- 2D Crystal Consortium, Materials Research Institute, Pennsylvania State University, University Park, PA, 16802, USA
| | - Yew San Hor
- Department of Physics, Missouri University of Science and Technology, Rolla, MO, 65409, USA
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland
| | - Marek Bartkowiak
- Laboratory for Neutron and Muon Instrumentation, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Matthias Hecker
- Institute for Theory of Condensed Matter and Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Jörg Schmalian
- Institute for Theory of Condensed Matter and Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Rolf Lortz
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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17
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Guguchia Z, Verezhak JAT, Gawryluk DJ, Tsirkin SS, Yin JX, Belopolski I, Zhou H, Simutis G, Zhang SS, Cochran TA, Chang G, Pomjakushina E, Keller L, Skrzeczkowska Z, Wang Q, Lei HC, Khasanov R, Amato A, Jia S, Neupert T, Luetkens H, Hasan MZ. Tunable anomalous Hall conductivity through volume-wise magnetic competition in a topological kagome magnet. Nat Commun 2020; 11:559. [PMID: 31992705 PMCID: PMC6987130 DOI: 10.1038/s41467-020-14325-w] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 12/17/2019] [Indexed: 11/23/2022] Open
Abstract
Magnetic topological phases of quantum matter are an emerging frontier in physics and material science. Along these lines, several kagome magnets have appeared as the most promising platforms. Here, we explore magnetic correlations in the kagome magnet Co3Sn2S2. Using muon spin-rotation, we present evidence for competing magnetic orders in the kagome lattice of this compound. Our results show that while the sample exhibits an out-of-plane ferromagnetic ground state, an in-plane antiferromagnetic state appears at temperatures above 90 K, eventually attaining a volume fraction of 80% around 170 K, before reaching a non-magnetic state. Strikingly, the reduction of the anomalous Hall conductivity (AHC) above 90 K linearly follows the disappearance of the volume fraction of the ferromagnetic state. We further show that the competition of these magnetic phases is tunable through applying either an external magnetic field or hydrostatic pressure. Our results taken together suggest the thermal and quantum tuning of Berry curvature induced AHC via external tuning of magnetic order.
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Affiliation(s)
- Z Guguchia
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland.
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
| | - J A T Verezhak
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - D J Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - S S Tsirkin
- Department of Physics, University of Zürich, Winterthurerstrasse 190, Zurich, Switzerland
| | - J-X Yin
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - I Belopolski
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - H Zhou
- International Center for Quantum Materials and School of Physics, Peking University, Beijing, China
- CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Science, Beijing, China
| | - G Simutis
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - S-S Zhang
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - T A Cochran
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - G Chang
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - E Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - L Keller
- Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Z Skrzeczkowska
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - Q Wang
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing, China
| | - H C Lei
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing, China
| | - R Khasanov
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - A Amato
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - S Jia
- International Center for Quantum Materials and School of Physics, Peking University, Beijing, China
- CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Science, Beijing, China
| | - T Neupert
- Department of Physics, University of Zürich, Winterthurerstrasse 190, Zurich, Switzerland
| | - H Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland.
| | - M Z Hasan
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
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18
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Puphal P, Pomjakushin V, Kanazawa N, Ukleev V, Gawryluk DJ, Ma J, Naamneh M, Plumb NC, Keller L, Cubitt R, Pomjakushina E, White JS. Topological Magnetic Phase in the Candidate Weyl Semimetal CeAlGe. Phys Rev Lett 2020; 124:017202. [PMID: 31976692 DOI: 10.1103/physrevlett.124.017202] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 11/01/2019] [Indexed: 06/10/2023]
Abstract
We report the discovery of topological magnetism in the candidate magnetic Weyl semimetal CeAlGe. Using neutron scattering we find this system to host several incommensurate, square-coordinated multi-k[over →] magnetic phases below T_{N}. The topological properties of a phase stable at intermediate magnetic fields parallel to the c axis are suggested by observation of a topological Hall effect. Our findings highlight CeAlGe as an exceptional system for exploiting the interplay between the nontrivial topologies of the magnetization in real space and Weyl nodes in momentum space.
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Affiliation(s)
- Pascal Puphal
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Vladimir Pomjakushin
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Naoya Kanazawa
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
| | - Victor Ukleev
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Dariusz J Gawryluk
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Junzhang Ma
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - Muntaser Naamneh
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - Nicholas C Plumb
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Robert Cubitt
- Institut Laue-Langevin (ILL), 71 avenue des Martyrs, CS 20156, 38042 Grenoble cedex 9, France
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Jonathan S White
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
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19
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Li F, Pomjakushin V, Sibille R, Rössli B, Pomjakushina E. Revisiting the magnetic structure of R
1/3Sr 2/3FeO 3 ( R = La, Pr, Nd) by neutron powder and single-crystal diffraction combined with spherical polarimetry. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319091617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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20
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Puphal P, Pomjakushin V, Gawryluk D, Keller L, Pomjakushina E, White JS. Superspace magnetic structure and topological charges in Weyl semimetal CeAlGe. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319091642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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21
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Maity SR, Ceretti M, Keller L, Schefer J, Shang T, Pomjakushina E, Meven M, Sheptyakov D, Cervellino A, Paulus W. Structural disorder and magnetic correlations driven by oxygen doping in Nd 2NiO 4.11. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319091630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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22
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Svitlyk V, Garbarino G, Rosa AD, Pomjakushina E, Krzton-Maziopa A, Conder K, Nunez-Regueiro M, Mezouar M. High-pressure polymorphism of BaFe 2Se 3. J Phys Condens Matter 2019; 31:085401. [PMID: 30530951 DOI: 10.1088/1361-648x/aaf777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
BaFe2Se3 is a potential superconductor material exhibiting transition at 11 K and ambient pressure. Here we extended the structural and performed electrical resistivity measurements on this compound up to 51 GPa and 20 GPa, respectively, in order to distinguish if the superconductivity in this sample is intrinsic to the BaFe2Se3 phase or if it is originating from minor FeSe impurities that show a similar superconductive transition temperature. The electrical resistance measurements as a function of pressure show that at 5 GPa the superconducting transition is observed at around 10 K, similar to the one previously observed for this sample at ambient pressure. This indicates that the superconductivity in this sample is most likely intrinsic to the BaFe2Se3 phase and not to FeSe with T c > 20 K at these pressures. Further increase in pressure suppressed the superconductive signal and the sample remained in an insulating state up to the maximum achieved pressure of 20 GPa. Single-crystal and powder x-ray diffraction measurements revealed two structural transformations in BaFe2Se3: a second order transition above 3.5 GPa from Pnma (CsAg2I3-type structure) to Cmcm (CsCu2Cl3-type structure) and a first order transformation at 16.6 GPa. Here, γ-BaFe2Se3 transforms into δ-BaFe2Se3 (Cmcm, CsCu2Cl3-type average structure) via a first order phase transition mechanism. This transition is characterized by a significant shortening of the b lattice parameter of γ-BaFe2Se3 (17%) and accompanied by an anisotropic expansion in the orthogonal ac plane at the transition point.
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Affiliation(s)
- V Svitlyk
- European Synchrotron Radiation Facility, 38000 Grenoble, France
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23
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Shang T, Smidman M, Ghosh SK, Baines C, Chang LJ, Gawryluk DJ, Barker JAT, Singh RP, Paul DM, Balakrishnan G, Pomjakushina E, Shi M, Medarde M, Hillier AD, Yuan HQ, Quintanilla J, Mesot J, Shiroka T. Time-Reversal Symmetry Breaking in Re-Based Superconductors. Phys Rev Lett 2018; 121:257002. [PMID: 30608781 DOI: 10.1103/physrevlett.121.257002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 07/30/2018] [Indexed: 06/09/2023]
Abstract
To trace the origin of time-reversal symmetry breaking (TRSB) in Re-based superconductors, we performed comparative muon-spin rotation and relaxation (μSR) studies of superconducting noncentrosymmetric Re_{0.82}Nb_{0.18} (T_{c}=8.8 K) and centrosymmetric Re (T_{c}=2.7 K). In Re_{0.82}Nb_{0.18}, the low-temperature superfluid density and the electronic specific heat evidence a fully gapped superconducting state, whose enhanced gap magnitude and specific-heat discontinuity suggest a moderately strong electron-phonon coupling. In both Re_{0.82}Nb_{0.18} and pure Re, the spontaneous magnetic fields revealed by zero-field μSR below T_{c} indicate time-reversal symmetry breaking and thus unconventional superconductivity. The concomitant occurrence of TRSB in centrosymmetric Re and noncentrosymmetric ReT (T=transition metal), yet its preservation in the isostructural noncentrosymmetric superconductors Mg_{10}Ir_{19}B_{16} and Nb_{0.5}Os_{0.5}, strongly suggests that the local electronic structure of Re is crucial for understanding the TRSB superconducting state in Re and ReT. We discuss the superconducting order parameter symmetries that are compatible with the experimental observations.
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Affiliation(s)
- T Shang
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, Villigen CH-5232, Switzerland
- Swiss Light Source, Paul Scherrer Institut, Villigen CH-5232, Switzerland
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
| | - M Smidman
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
| | - S K Ghosh
- School of Physical Sciences, University of Kent, Canterbury CT2 7NH, United Kingdom
| | - C Baines
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - L J Chang
- Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan
| | - D J Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, Villigen CH-5232, Switzerland
| | - J A T Barker
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - R P Singh
- Indian Institute of Science Education and Research Bhopal, Bhopal, 462066, India
| | - D McK Paul
- Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - G Balakrishnan
- Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - E Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, Villigen CH-5232, Switzerland
| | - M Shi
- Swiss Light Source, Paul Scherrer Institut, Villigen CH-5232, Switzerland
| | - M Medarde
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, Villigen CH-5232, Switzerland
| | - A D Hillier
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxfordshire, OX11 0QX, United Kingdom
| | - H Q Yuan
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing Univeristy, Nanjing 210093, China
| | - J Quintanilla
- School of Physical Sciences, University of Kent, Canterbury CT2 7NH, United Kingdom
| | - J Mesot
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
- Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zurich, Switzerland
| | - T Shiroka
- Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zurich, Switzerland
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24
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Shang T, Canévet E, Morin M, Sheptyakov D, Fernández-Díaz MT, Pomjakushina E, Medarde M. Design of magnetic spirals in layered perovskites: Extending the stability range far beyond room temperature. Sci Adv 2018; 4:eaau6386. [PMID: 30397653 PMCID: PMC6203228 DOI: 10.1126/sciadv.aau6386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 09/19/2018] [Indexed: 06/08/2023]
Abstract
In insulating materials with ordered magnetic spiral phases, ferroelectricity can emerge owing to the breaking of inversion symmetry. This property is of both fundamental and practical interest, particularly with a view to exploiting it in low-power electronic devices. Advances toward technological applications have been hindered, however, by the relatively low ordering temperatures T spiral of most magnetic spiral phases, which rarely exceed 100 K. We have recently established that the ordering temperature of a magnetic spiral can be increased up to 310 K by the introduction of chemical disorder. Here, we explore the design space opened up by this novel mechanism by combining it with a targeted lattice control of some magnetic interactions. In Cu-Fe layered perovskites, we obtain T spiral values close to 400 K, comfortably far from room temperature and almost 100 K higher than using chemical disorder alone. Moreover, we reveal a linear relationship between the spiral's wave vector and the onset temperature of the spiral phase. This linear law ends at a paramagnetic-collinear-spiral triple point, which defines the highest spiral ordering temperature that can be achieved in this class of materials. On the basis of these findings, we propose a general set of rules for designing magnetic spirals in layered perovskites using external pressure, chemical substitutions, and/or epitaxial strain, which should guide future efforts to engineer magnetic spiral phases with ordering temperatures suitable for technological applications.
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Affiliation(s)
- Tian Shang
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Emmanuel Canévet
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Mickaël Morin
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Excelsus Structural Solutions (Swiss) AG PARK innovAARE, CH-5234 Villigen, Switzerland
| | - Denis Sheptyakov
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | | | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Marisa Medarde
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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25
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Xu N, Wang ZW, Magrez A, Bugnon P, Berger H, Matt CE, Strocov VN, Plumb NC, Radovic M, Pomjakushina E, Conder K, Dil JH, Mesot J, Yu R, Ding H, Shi M. Evidence of a Coulomb-Interaction-Induced Lifshitz Transition and Robust Hybrid Weyl Semimetal in T_{d}-MoTe_{2}. Phys Rev Lett 2018; 121:136401. [PMID: 30312078 DOI: 10.1103/physrevlett.121.136401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 07/16/2018] [Indexed: 06/08/2023]
Abstract
Using soft x-ray angle-resolved photoemission spectroscopy we probed the bulk electronic structure of T_{d}-MoTe_{2}. We found that on-site Coulomb interaction leads to a Lifshitz transition, which is essential for a precise description of the electronic structure. A hybrid Weyl semimetal state with a pair of energy bands touching at both type-I and type-II Weyl nodes is indicated by comparing the experimental data with theoretical calculations. Unveiling the importance of Coulomb interaction opens up a new route to comprehend the unique properties of MoTe_{2}, and is significant for understanding the interplay between correlation effects, strong spin-orbit coupling and superconductivity in this van der Waals material.
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Affiliation(s)
- N Xu
- Institute of Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Z W Wang
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - A Magrez
- Institute of Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - P Bugnon
- Institute of Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - H Berger
- Institute of Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - C E Matt
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Laboratory for Solid State Physics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - V N Strocov
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - N C Plumb
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Radovic
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - E Pomjakushina
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - K Conder
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - J H Dil
- Institute of Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - J Mesot
- Institute of Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Laboratory for Solid State Physics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - R Yu
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - H Ding
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
| | - M Shi
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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26
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Bran-Anleu P, Caruso F, Wangler T, Pomjakushina E, Flatt RJ. Standard and sample preparation for the micro XRF quantification of chlorides in hardened cement pastes. Microchem J 2018. [DOI: 10.1016/j.microc.2018.05.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Pomjakushina E, Rolfs K, Karpinski J, Conder K, Pomjakushin V. Neutron powder diffraction study of Tm 2Mn 2O 7 and Y 2Mn 2O 7 – pyrochlore obtained by yet another chemical route of synthesis. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s205327331809023x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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28
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Li F, Pomjakushin V, Sibille R, Yadav R, Keller L, Medarde M, Conder K, Pomjakushina E. Revisiting the magnetic structure of La 1/3Sr 2/3FeO 3 by neutron powder diffraction. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s2053273318093701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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29
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Giblin SR, Twengström M, Bovo L, Ruminy M, Bartkowiak M, Manuel P, Andresen JC, Prabhakaran D, Balakrishnan G, Pomjakushina E, Paulsen C, Lhotel E, Keller L, Frontzek M, Capelli SC, Zaharko O, McClarty PA, Bramwell ST, Henelius P, Fennell T. Pauling Entropy, Metastability, and Equilibrium in Dy_{2}Ti_{2}O_{7} Spin Ice. Phys Rev Lett 2018; 121:067202. [PMID: 30141658 DOI: 10.1103/physrevlett.121.067202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Indexed: 06/08/2023]
Abstract
Determining the fate of the Pauling entropy in the classical spin ice material Dy_{2}Ti_{2}O_{7} with respect to the third law of thermodynamics has become an important test case for understanding the existence and stability of ice-rule states in general. The standard model of spin ice-the dipolar spin ice model-predicts an ordering transition at T≈0.15 K, but recent experiments by Pomaranski et al. suggest an entropy recovery over long timescales at temperatures as high as 0.5 K, much too high to be compatible with the theory. Using neutron scattering and specific heat measurements at low temperatures and with long timescales (0.35 K/10^{6} s and 0.5 K/10^{5} s, respectively) on several isotopically enriched samples, we find no evidence of a reduction of ice-rule correlations or spin entropy. High-resolution simulations of the neutron structure factor show that the spin correlations remain well described by the dipolar spin ice model at all temperatures. Furthermore, by careful consideration of hyperfine contributions, we conclude that the original entropy measurements of Ramirez et al. are, after all, essentially correct: The short-time relaxation method used in that study gives a reasonably accurate estimate of the equilibrium spin ice entropy due to a cancellation of contributions.
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Affiliation(s)
- S R Giblin
- School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, United Kingdom
| | - M Twengström
- Department of Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | - L Bovo
- London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, 17-19 Gordon Street, London, WC1H OAH, United Kingdom
- Department of Innovation and Enterprise, University College London, 90 Tottenham Court Road, Fitzrovia, London W1T 4TJ, United Kingdom
| | - M Ruminy
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Bartkowiak
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - P Manuel
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, United Kingdom
| | - J C Andresen
- Department of Physics, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| | - D Prabhakaran
- Clarendon Laboratory, Physics Department, Oxford University, Oxford, OX1 3PU, United Kingdom
| | - G Balakrishnan
- Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - E Pomjakushina
- Laboratory for Scientific Developments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - C Paulsen
- Institut Néel, C.N.R.S-Université Joseph Fourier, B.P. 166, 38042 Grenoble, France
| | - E Lhotel
- Institut Néel, C.N.R.S-Université Joseph Fourier, B.P. 166, 38042 Grenoble, France
| | - L Keller
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Frontzek
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - S C Capelli
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, United Kingdom
| | - O Zaharko
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - P A McClarty
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany
| | - S T Bramwell
- London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, 17-19 Gordon Street, London, WC1H OAH, United Kingdom
| | - P Henelius
- Department of Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | - T Fennell
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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30
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Guguchia Z, Roessli B, Khasanov R, Amato A, Pomjakushina E, Conder K, Uemura YJ, Tranquada JM, Keller H, Shengelaya A. Complementary Response of Static Spin-Stripe Order and Superconductivity to Nonmagnetic Impurities in Cuprates. Phys Rev Lett 2017; 119:087002. [PMID: 28952761 DOI: 10.1103/physrevlett.119.087002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Indexed: 06/07/2023]
Abstract
We report muon-spin rotation and neutron-scattering experiments on nonmagnetic Zn impurity effects on the static spin-stripe order and superconductivity of the La214 cuprates. Remarkably, it was found that, for samples with hole doping x≈1/8, the spin-stripe ordering temperature T_{so} decreases linearly with Zn doping y and disappears at y≈4%, demonstrating a high sensitivity of static spin-stripe order to impurities within a CuO_{2} plane. Moreover, T_{so} is suppressed by Zn in the same manner as the superconducting transition temperature T_{c} for samples near optimal hole doping. This surprisingly similar sensitivity suggests that the spin-stripe order is dependent on intertwining with superconducting correlations.
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Affiliation(s)
- Z Guguchia
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - B Roessli
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - R Khasanov
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - A Amato
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - E Pomjakushina
- Laboratory for scientific developments and novel materials, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - K Conder
- Laboratory for scientific developments and novel materials, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Y J Uemura
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - J M Tranquada
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - H Keller
- Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - A Shengelaya
- Department of Physics, Tbilisi State University, Chavchavadze 3, GE-0128 Tbilisi, Georgia
- Andronikashvili Institute of Physics, I. Javakhishvili Tbilisi State University, Tamarashvili Street 6, 0177 Tbilisi, Georgia
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31
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Xu N, Autès G, Matt CE, Lv BQ, Yao MY, Bisti F, Strocov VN, Gawryluk D, Pomjakushina E, Conder K, Plumb NC, Radovic M, Qian T, Yazyev OV, Mesot J, Ding H, Shi M. Distinct Evolutions of Weyl Fermion Quasiparticles and Fermi Arcs with Bulk Band Topology in Weyl Semimetals. Phys Rev Lett 2017; 118:106406. [PMID: 28339253 DOI: 10.1103/physrevlett.118.106406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Indexed: 06/06/2023]
Abstract
The Weyl semimetal phase is a recently discovered topological quantum state of matter characterized by the presence of topologically protected degeneracies near the Fermi level. These degeneracies are the source of exotic phenomena, including the realization of chiral Weyl fermions as quasiparticles in the bulk and the formation of Fermi arc states on the surfaces. Here, we demonstrate that these two key signatures show distinct evolutions with the bulk band topology by performing angle-resolved photoemission spectroscopy, supported by first-principles calculations, on transition-metal monophosphides. While Weyl fermion quasiparticles exist only when the chemical potential is located between two saddle points of the Weyl cone features, the Fermi arc states extend in a larger energy scale and are robust across the bulk Lifshitz transitions associated with the recombination of two nontrivial Fermi surfaces enclosing one Weyl point into a single trivial Fermi surface enclosing two Weyl points of opposite chirality. Therefore, in some systems (e.g., NbP), topological Fermi arc states are preserved even if Weyl fermion quasiparticles are absent in the bulk. Our findings not only provide insight into the relationship between the exotic physical phenomena and the intrinsic bulk band topology in Weyl semimetals, but also resolve the apparent puzzle of the different magnetotransport properties observed in TaAs, TaP, and NbP, where the Fermi arc states are similar.
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Affiliation(s)
- N Xu
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - G Autès
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- National Centre for Computational Design and Discovery of Novel Materials MARVEL, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - C E Matt
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - B Q Lv
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - M Y Yao
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - F Bisti
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - V N Strocov
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - D Gawryluk
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - E Pomjakushina
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - K Conder
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - N C Plumb
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Radovic
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - T Qian
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - O V Yazyev
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- National Centre for Computational Design and Discovery of Novel Materials MARVEL, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - J Mesot
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Laboratory for Solid State Physics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - H Ding
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
| | - M Shi
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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32
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Morin M, Canévet E, Raynaud A, Bartkowiak M, Sheptyakov D, Ban V, Kenzelmann M, Pomjakushina E, Conder K, Medarde M. Tuning magnetic spirals beyond room temperature with chemical disorder. Nat Commun 2016; 7:13758. [PMID: 27982127 PMCID: PMC5171853 DOI: 10.1038/ncomms13758] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 10/31/2016] [Indexed: 11/15/2022] Open
Abstract
In the past years, magnetism-driven ferroelectricity and gigantic magnetoelectric effects have been reported for a number of frustrated magnets featuring ordered spiral magnetic phases. Such materials are of high-current interest due to their potential for spintronics and low-power magnetoelectric devices. However, their low-magnetic ordering temperatures (typically <100 K) greatly restrict their fields of application. Here we demonstrate that the onset temperature of the spiral phase in the perovskite YBaCuFeO5 can be increased by more than 150 K through a controlled manipulation of the Fe/Cu chemical disorder. Moreover, we show that this novel mechanism can stabilize the magnetic spiral state of YBaCuFeO5 above the symbolic value of 25 °C at zero magnetic field. Our findings demonstrate that the properties of magnetic spirals, including its wavelength and stability range, can be engineered through the control of chemical disorder, offering a great potential for the design of materials with magnetoelectric properties beyond room temperature.
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Affiliation(s)
- Mickaël Morin
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Emmanuel Canévet
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Adrien Raynaud
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Marek Bartkowiak
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Denis Sheptyakov
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Voraksmy Ban
- Swiss Light Source, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Michel Kenzelmann
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Kazimierz Conder
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Marisa Medarde
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
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33
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Li F, Gawryluk DJ, Pomjakushina E, Conder K. High pressure synthesis of iron complex oxides in high oxidation state (Fe 4+, Fe 5+): mapping between localized and itinerant behavior. Acta Crystallogr A Found Adv 2016. [DOI: 10.1107/s2053273316095826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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34
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Medarde M, Medarde M, Mena M, Gavilano J, Pomjakushina E, Kamazawa K, Pomjakushin V, Sheptyakov D, Batlogg B, Ott HR, Mansson M, Juranyi F. Experimental visualization of the Na diffusion paths in Na 0.7CoO 2, a prospective cathode material for Na-ion batteries. Acta Crystallogr A Found Adv 2016. [DOI: 10.1107/s2053273316095668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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35
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Krzton-Maziopa A, Svitlyk V, Pomjakushina E, Puzniak R, Conder K. Superconductivity in alkali metal intercalated iron selenides. J Phys Condens Matter 2016; 28:293002. [PMID: 27248118 DOI: 10.1088/0953-8984/28/29/293002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Alkali metal intercalated iron selenide superconductors A x Fe2-y Se2 (where A = K, Rb, Cs, Tl/K, and Tl/Rb) are characterized by several unique properties, which were not revealed in other superconducting materials. The compounds crystallize in overall simple layered structure with FeSe layers intercalated with alkali metal. The structure turned out to be pretty complex as the existing Fe-vacancies order below ~550 K, which further leads to an antiferromagnetic ordering with Néel temperature fairly above room temperature. At even lower temperatures a phase separation is observed. While one of these phases stays magnetic down to the lowest temperatures the second is becoming superconducting below ~30 K. All these effects give rise to complex relationships between the structure, magnetism and superconductivity. In particular the iron vacancy ordering, linked with a long-range magnetic order and a mesoscopic phase separation, is assumed to be an intrinsic property of the system. Since the discovery of superconductivity in those compounds in 2010 they were investigated very extensively. Results of the studies conducted using a variety of experimental techniques and performed during the last five years were published in hundreds of reports. The present paper reviews scientific work concerning methods of synthesis and crystal growth, structural and superconducting properties as well as pressure investigations.
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Affiliation(s)
- A Krzton-Maziopa
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, PL-00-664 Warsaw, Poland
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Abstract
In this work, we present a new chemical route to synthesize Tm2Mn2O7 pyrochlore, which a compound that is thermodynamically unstable at ambient pressure. Differently from the reported in the past high-pressure synthesis of the same compound applying oxides as starting materials, we have obtained a pure Tm2Mn2O7 phase by a converting TmMnO3 at 1100 °C and an oxygen pressure of 1300 bar. The studies of Tm2Mn2O7 performed by a high-resolution neutron powder diffraction have shown that a pure pyrochlore cubic phase Tm2Mn2O7 (space group Fd3¯m) have been obtained. Upon cooling below 25 K, there is a transition to a ferromagnetically (FM) ordered phase observed with an additional antiferromagnetic (AFM) canting, suggesting a lowering of the initial cubic crystal symmetry. The magnetic transition is accompanied by a small but very visible magnetostriction effect. Using symmetry analysis, we have found a solution for the AFM structure in the maximal Shubnikov subgroup I41/am'd'.
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Affiliation(s)
- Ekaterina Pomjakushina
- Laboratory for Developments and Methods, Paul Scherrer Institut (PSI) , 5232 Villigen, Switzerland
| | - Vladimir Pomjakushin
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut (PSI) , 5232 Villigen, Switzerland
| | - Katharina Rolfs
- Laboratory for Developments and Methods, Paul Scherrer Institut (PSI) , 5232 Villigen, Switzerland
| | - Janusz Karpinski
- Laboratory for Developments and Methods, Paul Scherrer Institut (PSI) , 5232 Villigen, Switzerland
| | - Kazimierz Conder
- Laboratory for Developments and Methods, Paul Scherrer Institut (PSI) , 5232 Villigen, Switzerland
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37
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Juranyi F, Månsson M, Gavilano JL, Mena M, Pomjakushina E, Medarde M, Sugiyama J, Kamazawa K, Batlogg B, Ott HR, Seydel T. Dynamics across the structural transitions at elevated temperatures in Na0.7CoO2. EPJ Web of Conferences 2015. [DOI: 10.1051/epjconf/20158302008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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38
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Zayed ME, Rüegg C, Strässle T, Stuhr U, Roessli B, Ay M, Mesot J, Link P, Pomjakushina E, Stingaciu M, Conder K, Rønnow HM. Correlated decay of triplet excitations in the Shastry-Sutherland compound SrCu2(BO3)2. Phys Rev Lett 2014; 113:067201. [PMID: 25148346 DOI: 10.1103/physrevlett.113.067201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Indexed: 06/03/2023]
Abstract
The temperature dependence of the gapped triplet excitations (triplons) in the 2D Shastry-Sutherland quantum magnet SrCu(2)(BO(3))(2) is studied by means of inelastic neutron scattering. The excitation amplitude rapidly decreases as a function of temperature, while the integrated spectral weight can be explained by an isolated dimer model up to 10 K. Analyzing this anomalous spectral line shape in terms of damped harmonic oscillators shows that the observed damping is due to a two-component process: one component remains sharp and resolution limited while the second broadens. We explain the underlying mechanism through a simple yet quantitatively accurate model of correlated decay of triplons: an excited triplon is long lived if no thermally populated triplons are nearby but decays quickly if there are. The phenomenon is a direct consequence of frustration induced triplon localization in the Shastry-Sutherland lattice.
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Affiliation(s)
- M E Zayed
- Department of Mathematics, Statistics and Physics, College of Arts and Science, Qatar University, P.O. Box 2713, Doha, Qatar and Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland and Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Ch Rüegg
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland and DPMC-MaNEP, University of Geneva, CH-1211 Geneva, Switzerland and London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - Th Strässle
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - U Stuhr
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - B Roessli
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - M Ay
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - J Mesot
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland and Laboratory for Neutron and Synchrotron Spectroscopy, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland and Laboratory for Solid State Physics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - P Link
- Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM-2), D-85747 Garching, Germany
| | - E Pomjakushina
- Laboratory for Developments and Methods, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - M Stingaciu
- Laboratory for Developments and Methods, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - K Conder
- Laboratory for Developments and Methods, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - H M Rønnow
- Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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Morin M, Scheptyakov D, Keller L, Rodríguez-Carvajal J, Scaramucci A, Spaldin N, Kenzelmann M, Pomjakushina E, Conder K, Medarde M. Electric polarization from spiral order below 200K in multiferroic YBaCuFeO 5. Acta Crystallogr A Found Adv 2014. [DOI: 10.1107/s2053273314096119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Ferroelectric materials have been known for almost one century [1]. While their potential for applications was rapidly recognized, the possibility of combining ferroelectricity with magnetic order -preferably with ferromagnetism- has resulted in an enormous deal of interest during the last decade. Several new materials combining both types of order have been recently reported, although their promising multifunctionalities have been obscured by two facts: on one side, most of them are antiferromagnetic; on the other, their transition temperatures, typically below 40K, are too low for most practical applications. The oxygen-defficient double perovskite YBaFeCuO5 constitutes a remarkable exception. Spontaneous electric polarization has been recently reported to exist below an unusually high temperature of TC ≍ 200K [2] coinciding with the occurrence of a commensurate - to - incommensurate reorientation of the Fe3+ and Cu2+ magnetic moments [3,4]. From a more fundamental point of view the observation of incommensurable magnetic order in a tetragonal material at such high temperatures is rather surprising. In particular, the nature of the relevant competing magnetic interactions and its possible link to low dimensionality or geometrical frustration is not understood at present. Although the existence of the spin reorientation in this material is known since 1995 [3] the low temperature magnetic structure has not yet been solved. Using neutron powder diffraction we have recently been able to propose a spiral model which satisfactorily describes the measured magnetic intensities below TC. Further, investigation of the crystal structure showed the existence of small anomalies in the lattice parameters and some interatomic distances at TC. The relevance of these findings for the magnetoelectric coupling, the direction of the polarization, the modification of the different exchange paths in the structure and the stabilization of the incommensurate magnetic order below TC is discussed.
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40
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Pomjakushina E, Krzton-Maziopa A, Pomjakushin V, Bosak A, Chernyshov D, Svitlyk V, Dmitriev V, Speller S, Conder K. Phase separation in AyFe 2-xSe 2(A= K, Rb, Cs) superconductors. Acta Crystallogr A Found Adv 2014. [DOI: 10.1107/s2053273314085350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The interplay between superconductivity, magnetism and crystal structure in iron-based superconductors has attracted a great interest in the recent years as it is considered to be the key for understanding the mechanisms responsible for high temperature superconductivity. Alkali metal intercalated iron chalcogenide superconductors (A122) exhibit unique behavior which is not observed in other iron-based superconducting materials such as antiferromagnetic ordering above room temperature and iron vacancies ordering. These materials have complex crystal structures with several phase transitions and are mixtures of phases even in the form usually described as a single crystal. A pronounced reversible phase separation revealed in A122 single crystals, as well as controversies regarding the origin of superconductivity and the stoichiometry and symmetry of the superconducting phase are still in the forefront of scientific activity. Here we will present a diffraction study of the crystal structures, antiferromagnetic ordering and intrinsic phase separation in alkali-metal iron chalcogenides [1]. The complementary scanning electron microscope study, including high-resolution electron back-scatter diffraction mapping will be also presented [2].
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Medarde M, Mena M, Gavilano J, Pomjakushina E, Sugiyama J, Kamazawa K, Pomjakushin V, Sheptyakov D, Battlog B, Ott HR, Mansson M, Juranyi F. 1D to 2D Na-Ion Diffusion Linked to Structural Transitions in Na 0.7CoO 2. Acta Crystallogr A Found Adv 2014. [DOI: 10.1107/s2053273314096363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
One of the most important scientific problems faced by our society is how to convert and store clean energy. In order to achieve a significant progress in this field we need to understand the fundamental dynamical processes that govern the transfer of energy on an atomic scale. For many energy devices such as solid-state batteries and solid-oxide fuel cells, this means understanding and controlling the complex mechanisms of ion diffusion in solid matter. Because of the unusual evolution of correlated electronic properties (frustrated magnetism and superconductivity), the layered Co-oxide family NaxCoO2 (0<x<1), object of this work, has been extensively studied during the last decade. More recently it has also attracted the attention of applied sciences, mainly because of its structural similarity with LixCoO2, one of the most common Li-ion battery electrodes. In view of the larger abundance of Na in the earth crust with respect to Li, Na-ion batteries enjoy an increased attention. Hence we decided to investigate the Na-ion diffusion in this material, whose possible use as cathode for solid-state rechargeable batteries has recently been proposed [1]. The present study reports the observation of a crossover from quasi-1D to 2D Na-ion diffusion in Na0.7CoO2. High resolution neutron powder diffraction data indicate the existence of two structural transitions at T1=290K and T2=400K [2]. We present here evidence indicating that both transitions are closely related to changes in the Na-ion mobility. Analysis of the anomalies in the Na-Na distances, the Debye-Waller factors and the scattering density in the paths connecting neighbouring Na sites strongly suggest that Na-ion diffusion starts at T1, although for T1<T<T2 it occurs preferentially along quasi-1D paths. A fully isotropic diffusion is only observed for T>T2, coinciding with the equalization of all first-neighbor Na-Na distances in the structure [2]. These findings provide new insight on the subtle mechanisms controlling the Na-ion diffusion in the NaxCoO2 family and could be used for the design of related energy materials with improved functional properties. Fig. 1. Fourier difference maps of the z = 0.25 Na planes at T = 50, 320 and 450 K showing the evolution of the residual scattering density in the paths connecting the Na1 and Na2 sites (from ref.[2]).
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Guguchia Z, Khasanov R, Bendele M, Pomjakushina E, Conder K, Shengelaya A, Keller H. Negative oxygen isotope effect on the static spin stripe order in superconducting La(2-x)Ba(x)CuO(4) (x=1/8) observed by muon-spin rotation. Phys Rev Lett 2014; 113:057002. [PMID: 25126931 DOI: 10.1103/physrevlett.113.057002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Indexed: 06/03/2023]
Abstract
Large negative oxygen-isotope (^{16}O and ^{18}O) effects (OIEs) on the static spin-stripe-ordering temperature T_{so} and the magnetic volume fraction V_{m} were observed in La_{2-x}Ba_{x}CuO_{4}(x=1/8) by means of muon-spin-rotation experiments. The corresponding OIE exponents were found to be α_{T_{so}}=-0.57(6) and α_{V_{m}}=-0.71(9), which are sign reversed to α_{T_{c}}=0.46(6) measured for the superconducting transition temperature T_{c}. This indicates that the electron-lattice interaction is involved in the stripe formation and plays an important role in the competition between bulk superconductivity and static stripe order in the cuprates.
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Affiliation(s)
- Z Guguchia
- Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - R Khasanov
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - M Bendele
- Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - E Pomjakushina
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - K Conder
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - A Shengelaya
- Department of Physics, Tbilisi State University, Chavchavadze 3, GE-0128 Tbilisi, Georgia
| | - H Keller
- Physik-Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
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Xu N, Biswas PK, Dil JH, Dhaka RS, Landolt G, Muff S, Matt CE, Shi X, Plumb NC, Radović M, Pomjakushina E, Conder K, Amato A, Borisenko SV, Yu R, Weng HM, Fang Z, Dai X, Mesot J, Ding H, Shi M. Direct observation of the spin texture in SmB6 as evidence of the topological Kondo insulator. Nat Commun 2014; 5:4566. [PMID: 25074332 DOI: 10.1038/ncomms5566] [Citation(s) in RCA: 175] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/01/2014] [Indexed: 11/09/2022] Open
Abstract
Topological Kondo insulators have been proposed as a new class of topological insulators in which non-trivial surface states reside in the bulk Kondo band gap at low temperature due to strong spin-orbit coupling. In contrast to other three-dimensional topological insulators, a topological Kondo insulator is truly bulk insulating. Furthermore, strong electron correlations are present in the system, which may interact with the novel topological phase. By applying spin- and angle-resolved photoemission spectroscopy, here we show that the surface states of SmB6 are spin polarized. The spin is locked to the crystal momentum, fulfilling time reversal and crystal symmetries. Our results provide strong evidence that SmB6 can host topological surface states in a bulk insulating gap stemming from the Kondo effect, which can serve as an ideal platform for investigating of the interplay between novel topological quantum states with emergent effects and competing orders induced by strongly correlated electrons.
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Affiliation(s)
- N Xu
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - P K Biswas
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - J H Dil
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - R S Dhaka
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - G Landolt
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Physik-Institut, Universität Zürich, Winterthurerstrauss 190, CH-8057 Zürich, Switzerland
| | - S Muff
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - C E Matt
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Laboratory for Solid State Physics, ETH Zürich, CH-8093, Zürich, Switzerland
| | - X Shi
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - N C Plumb
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - M Radović
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] SwissFEL, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - E Pomjakushina
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - K Conder
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - A Amato
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - S V Borisenko
- Institute for Solid State Research, IFW Dresden, PO Box 270116, D-01171 Dresden, Germany
| | - R Yu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - H-M Weng
- 1] Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China [2] Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Z Fang
- 1] Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China [2] Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - X Dai
- 1] Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China [2] Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - J Mesot
- 1] Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland [2] Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland [3] Laboratory for Solid State Physics, ETH Zürich, CH-8093, Zürich, Switzerland
| | - H Ding
- 1] Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China [2] Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - M Shi
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
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Krzton-Maziopa A, Guguchia Z, Pomjakushina E, Pomjakushin V, Khasanov R, Luetkens H, Biswas PK, Amato A, Keller H, Conder K. Superconductivity in a new layered bismuth oxyselenide: LaO(0.5)F(0.5)BiSe₂. J Phys Condens Matter 2014; 26:215702. [PMID: 24805837 DOI: 10.1088/0953-8984/26/21/215702] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report superconductivity at T(c) ≈ 2.6 K in a new layered bismuth oxyselenide LaO(0.5)F(0.5)BiSe2 with the ZrCuSiAs-type structure composed of alternating superconducting BiSe2 and blocking LaO layers. The superconducting properties of LaO(0.5)F(0.5)BiSe2 were investigated by means of dc magnetization, resistivity and muon-spin rotation experiments, revealing the appearance of bulk superconductivity with a rather large superconducting volume fraction of ≈ 70% at 1.8 K.
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Affiliation(s)
- A Krzton-Maziopa
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland
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Reinle-Schmitt ML, Cancellieri C, Cavallaro A, Harrington GF, Leake SJ, Pomjakushina E, Kilner JA, Willmott PR. Chemistry and structure of homoepitaxial SrTiO3 films and their influence on oxide-heterostructure interfaces. Nanoscale 2014; 6:2598-2602. [PMID: 24473287 DOI: 10.1039/c3nr06456e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The properties of single-crystal SrTiO3 substrates and homoepitaxial SrTiO3 films grown by pulsed laser deposition have been compared, in order to understand the loss of interfacial conductivity when more than a critical thickness of nominally homoepitaxial SrTiO3 is inserted between a LaAlO3 film and a SrTiO3 substrate. In particular, the chemical composition and the structure of homoepitaxial SrTiO3 investigated by low-energy ion-scattering and surface X-ray diffraction show that for insulating heterointerfaces, a Sr-excess is present between the LaAlO3 and homoepitaxial SrTiO3. Furthermore, an increase in the out-of-plane lattice constant is observed in LaAlO3, indicating that the conductivity both with and without insertion of the SrTiO3 thin film originates from a Zener breakdown associated with the polar catastrophe. When more than a critical thickness of homoepitaxial SrTiO3 is inserted between LaAlO3 and SrTiO3, the electrons transferred by the electronic reconstruction are trapped by the formation of a Sr-rich secondary phase and Sr-vacancies. The migration of Sr towards the surface of homoepitaxial SrTiO3 and accompanying loss of interfacial conductivity can be delayed by reducing the Sr-content in the PLD target.
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Bendele M, Marini C, Joseph B, Simonelli L, Dore P, Pascarelli S, Chikovani M, Pomjakushina E, Conder K, Saini NL, Postorino P. Dispersive x-ray absorption studies at the Fe K-edge on the iron chalcogenide superconductor FeSe under pressure. J Phys Condens Matter 2013; 25:425704. [PMID: 24084478 DOI: 10.1088/0953-8984/25/42/425704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The local structure and the electronic properties of FeSe under hydrostatic pressure were studied by means of dispersive x-ray absorption measurements at the Fe K-edge. The pressure dependence of the x-ray absorption near edge structure features seems to follow the behavior of the superconducting transition temperature Tc. The local structure, that has an important impact on the superconducting properties, appears to fall into two regimes: the pressure dependence of the Fe-Fe bond distance shows a clear change in the compressibility at p ∼ 5 GPa; in contrast, the Fe-Se bond distance decreases continuously with increasing pressure with a lower compressibility than the Fe-Fe bond. The results suggest that the pressure dependent changes in Tc of FeSe are closely related to the changes in local structure.
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Affiliation(s)
- M Bendele
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 2, I-00185 Roma, Italy
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Svitlyk V, Chernyshov D, Pomjakushina E, Krzton-Maziopa A, Conder K, Pomjakushin V, Pöttgen R, Dmitriev V. Crystal structure of BaFe2Se3 as a function of temperature and pressure: phase transition phenomena and high-order expansion of Landau potential. J Phys Condens Matter 2013; 25:315403. [PMID: 23838324 DOI: 10.1088/0953-8984/25/31/315403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BaFe2Se3 (Pnma, CsAg2I3-type structure), recently assumed to show superconductivity at ~11 K, exhibits a pressure-dependent structural transition to the CsCu2Cl3-type structure (Cmcm space group) around 60 kbar, as evidenced from pressure-dependent synchrotron powder diffraction data. Temperature-dependent synchrotron powder diffraction data indicate an evolution of the room-temperature BaFe2Se3 structure towards a high-symmetry CsCu2Cl3 form upon heating. Around 425 K BaFe2Se3 undergoes a reversible, first-order isostructural transition, which is supported by the differential scanning calorimetry data. The temperature-dependent structural changes occur in two stages, as determined by the alignment of the FeSe4 tetrahedra and corresponding adjustments of the positions of Ba atoms. On further heating, a second-order phase transformation into the Cmcm structure is observed at 660 K. A rather unusual combination of isostructural and second-order phase transformations is parameterized within phenomenological theory assuming high-order expansion of the Landau potential. A generic phase diagram mapping observed structures is proposed on the basis of the parameterization.
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Affiliation(s)
- V Svitlyk
- Institut für Anorganische und Analytische Chemie, WWU Münster, Münster, Germany.
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48
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Medarde M, Mena M, Gavilano JL, Pomjakushina E, Sugiyama J, Kamazawa K, Pomjakushin VY, Sheptyakov D, Batlogg B, Ott HR, Månsson M, Juranyi F. 1D to 2D Na+ ion diffusion inherently linked to structural transitions in Na0.7CoO2. Phys Rev Lett 2013; 110:266401. [PMID: 23848903 DOI: 10.1103/physrevlett.110.266401] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 04/12/2013] [Indexed: 05/27/2023]
Abstract
We report the observation of a stepwise "melting" of the low-temperature Na-vacancy order in the layered transition-metal oxide Na0.7CoO2. High-resolution neutron powder diffraction analysis indicates the existence of two first-order structural transitions, one at T1≈290 K followed by a second at T2≈400 K. Detailed analysis strongly suggests that both transitions are linked to changes in the Na mobility. Our data are consistent with a two-step disappearance of Na-vacancy order through the successive opening of first quasi-1D (T1>T>T2) and then 2D (T>T2) Na diffusion paths. These results shed new light on previous, seemingly incompatible, experimental interpretations regarding the relationship between Na-vacancy order and Na dynamics in this material. They also represent an important step towards the tuning of physical properties and the design of tailored functional materials through an improved control and understanding of ionic diffusion.
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Affiliation(s)
- M Medarde
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
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Biswas PK, Krzton-Maziopa A, Khasanov R, Luetkens H, Pomjakushina E, Conder K, Amato A. Two-dimensional superfluid density in an alkali metal-organic solvent intercalated iron selenide superconductor Li(C5H5N)0.2Fe2Se2. Phys Rev Lett 2013; 110:137003. [PMID: 23581361 DOI: 10.1103/physrevlett.110.137003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 12/30/2012] [Indexed: 06/02/2023]
Abstract
We report the low-temperature electronic and magnetic properties of the alkali metal-organic solvent intercalated iron selenide superconductor Li(C5H5N)0.2Fe2Se2 using muon-spin-spectroscopy measurements. The zero-field muon spin relaxation (μSR) results indicate that nearly half of the sample is magnetically ordered and spatially phase separated from the superconducting region. The transverse-field μSR results reveal that the superfluid density of Li(C5H5N)0.2Fe2Se2 is two dimensional in nature. The temperature dependence of the penetration depth λ(T) can be explained using a two-gap s-wave model. This implies that, despite the 2D nature of the superfluid density, the symmetry of the superconducting gap remains unaltered to the parent compound FeSe.
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Affiliation(s)
- P K Biswas
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland.
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50
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Bosak A, Svitlyk V, Popov A, de Sanctis D, Pomjakushina E, Pomjakushin V, Krzton-Maziopa A, Conder K, Chernyshov D. Three-dimensional mapping of reciprocal space and structural complexity of AxFe 2−ySe 2superconductors ( A= Rb, Cs). Acta Crystallogr A 2012. [DOI: 10.1107/s0108767312096389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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