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Wang L, Wang S, Niu Y, Liu X, Wu Y, Zhang B, Liu Z, Li XP, Chen XQ. Intercalating Architecture for the Design of Charge Density Wave in Metallic MA 2Z 4 Materials. NANO LETTERS 2024; 24:11279-11285. [PMID: 39145763 DOI: 10.1021/acs.nanolett.4c02998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2024]
Abstract
We present a novel approach to induce charge density waves (CDWs) in metallic MA2Z4 materials, resembling the behavior observed in transition metal dichalcogenides (TMDCs). This method leverages the intercalating architecture to maintain the same crystal field and Fermi surface topologies. Our investigation reveals that CDW instability in these materials arises from electron-phonon coupling (EPC) between the d band and longitudinal acoustic (LA) phonons, mirroring TMDC's behavior. By combining α-MA2Z4 with 1H-MX2 materials in a predictive CDW phase diagram using critical EPC constants, we demonstrate the feasibility of extending CDW across material families with comparable crystal fields and reveal the crucial role in CDW instability of the competition between ionic charge transfer and electron correlation. We further uncover a strain-induced Mott transition in β2-NbGe2N4 monolayer featuring star-of-David patterns. This work highlights the potential of intercalating architecture to engineer CDW materials, expanding our understanding of CDW instability and correlation physics.
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Affiliation(s)
- Lei Wang
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - ShuaiYu Wang
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Yuekun Niu
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Xiuying Liu
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Yapeng Wu
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Bing Zhang
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Zhifeng Liu
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Xiao-Ping Li
- School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, People's Republic of China
| | - Xing-Qiu Chen
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, People's Republic of China
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2
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Jin H, Wei T, Huang B. Incognizant 1T/1H Charge-Density-Wave Phases in Monolayer NbTe 2. NANO LETTERS 2024; 24:10892-10898. [PMID: 39167086 DOI: 10.1021/acs.nanolett.4c02621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/23/2024]
Abstract
While experimental realization of multiple charge-density waves (CDWs) has been ascribed to monolayer 1T-NbTe2, their atomic structures are still largely unclear, preventing a deep understanding of their novel electronic structures. Here, comparing first-principles-calculated orbital textures with reported STM measurements, we successfully identify multiple CDWs in monolayer NbTe2. Surprisingly, we reveal that both 1T/1H phases could exist in monolayer NbTe2, which was incognizant before. Particularly, we find that the experimentally observed 4 × 1 and 4 × 4 CDWs could be attributed to 1H stacking, while the observed 19 × 19 phase could possess 1T stacking. The existence of 1T/1H phases results in competition between CDW, spin-density wave (SDW), and ferromagnetism in 1H stacking under an external field and results in CDW-induced quantum phase transitions from a Kramers-Weyl fermion to a topological insulator in 1T stacking. Our study suggests NbTe2 as an exotic platform to investigate the interplay between CDW, SDW, and topological phases, which are largely unexplored in current experiments.
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Affiliation(s)
- Heng Jin
- School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Tan Wei
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Bing Huang
- School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China
- Beijing Computational Science Research Center, Beijing 100193, China
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3
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Mahatha SK, Phillips J, Corral-Sertal J, Subires D, Korshunov A, Kar A, Buck J, Diekmann F, Garbarino G, Ivanov YP, Chuvilin A, Mondal D, Vobornik I, Bosak A, Rossnagel K, Pardo V, Fumega AO, Blanco-Canosa S. Self-Stacked 1T-1H Layers in 6R-NbSeTe and the Emergence of Charge and Magnetic Correlations Due to Ligand Disorder. ACS NANO 2024. [PMID: 39086092 DOI: 10.1021/acsnano.4c02005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
The emergence of correlated phenomena arising from the combination of 1T and 1H van der Waals layers is the focus of intense research. Here, we synthesize a self-stacked 6R phase in NbSeTe, showing perfect alternating 1T and 1H layers that grow coherently along the c-direction, as revealed by scanning transmission electron microscopy. Angle-resolved photoemission spectroscopy shows a mixed contribution of the trigonal and octahedral Nb bands to the Fermi level. Diffuse scattering reveals temperature-independent short-range charge fluctuations with propagation vector qCO = (0.25 0), derived from the condensation of a longitudinal mode in the 1T layer, while the long-range charge density wave is quenched by ligand disorder. Magnetization measurements suggest the presence of an inhomogeneous, short-range magnetic order, further supported by the absence of a clear phase transition in the specific heat. These experimental analyses in combination with ab initio calculations indicate that the ground state of 6R-NbSeTe is described by a statistical distribution of short-range charge-modulated and spin-correlated regions driven by ligand disorder. Our results demonstrate how natural 1T-1H self-stacked bulk heterostructures can be used to engineer emergent phases of matter.
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Affiliation(s)
- Sanjoy K Mahatha
- UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - Jan Phillips
- Departamento de Física Aplicada, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela, Spain
- Instituto de Materiais iMATUS, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela, Spain
| | - Javier Corral-Sertal
- Departamento de Física Aplicada, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela, Spain
- CiQUS, Centro Singular de Investigacion en Quimica Biolóxica e Materiais Moleculares, Departamento de Quimica-Fisica, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - David Subires
- Donostia International Physics Center (DIPC), E-20018 San Sebastián, Spain
- University of the Basque Country (UPV/EHU), Basque Country, Bilbao 48080 Spain
| | - Artem Korshunov
- European Synchrotron Radiation Facility (ESRF), BP 220, F-38043 Grenoble Cedex, France
| | - Arunava Kar
- Donostia International Physics Center (DIPC), E-20018 San Sebastián, Spain
| | - Jens Buck
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, D-24098 Kiel, Germany
| | - Florian Diekmann
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, D-24098 Kiel, Germany
| | - Gaston Garbarino
- European Synchrotron Radiation Facility (ESRF), BP 220, F-38043 Grenoble Cedex 9, France
| | - Yurii P Ivanov
- Electron Spectroscopy and Nanoscopy, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Andrey Chuvilin
- CIC Nanogune, E-20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Debashis Mondal
- Consiglio Nazionale delle Ricerche (CNR)- Istituto Officina dei Materiali (IOM), Laboratorio TASC in Area Science, 34149 Trieste, Italy
- Sovarani Memorial College, Jagatballavpur, Howrah 711408, India
| | - Ivana Vobornik
- Consiglio Nazionale delle Ricerche (CNR)- Istituto Officina dei Materiali (IOM), Laboratorio TASC in Area Science, 34149 Trieste, Italy
| | - Alexei Bosak
- European Synchrotron Radiation Facility (ESRF), BP 220, F-38043 Grenoble Cedex, France
| | - Kai Rossnagel
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Victor Pardo
- Departamento de Física Aplicada, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela, Spain
- Instituto de Materiais iMATUS, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela, Spain
| | - Adolfo O Fumega
- Department of Applied Physics, Aalto University, 02150 Espoo, Finland
| | - Santiago Blanco-Canosa
- Donostia International Physics Center (DIPC), E-20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
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Kalimuddin S, Chatterjee S, Bera A, Afzal H, Bera S, Roy DS, Das S, Debnath T, Bansal B, Mondal M. Exceptionally Slow, Long-Range, and Non-Gaussian Critical Fluctuations Dominate the Charge Density Wave Transition. PHYSICAL REVIEW LETTERS 2024; 132:266504. [PMID: 38996319 DOI: 10.1103/physrevlett.132.266504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 05/02/2024] [Accepted: 05/23/2024] [Indexed: 07/14/2024]
Abstract
(TaSe_{4})_{2}I is a well-studied quasi-one-dimensional compound long-known to have a charge-density wave (CDW) transition around 263 K. We argue that the critical fluctuations of the pinned CDW order parameter near the transition can be inferred from the resistance noise on account of their coupling to the dissipative normal carriers. Remarkably, the critical fluctuations of the CDW order parameter are slow enough to survive the thermodynamic limit and dominate the low-frequency resistance noise. The noise variance and relaxation time show rapid growth (critical opalescence and critical slowing down) within a temperature window of ϵ≈±0.1, where ϵ is the reduced temperature. This is very wide but consistent with the Ginzburg criterion. We further show that this resistance noise can be quantitatively used to extract the associated critical exponents. Below |ϵ|≲0.02, we observe a crossover from mean-field to a fluctuation-dominated regime with the critical exponents taking anomalously low values. The distribution of fluctuations in the critical transition region is skewed and strongly non-Gaussian. This non-Gaussianity is interpreted as the breakdown of the validity of the central limit theorem as the diverging coherence volume becomes comparable to the macroscopic sample size. The large magnitude critical fluctuations observed over an extended temperature range, as well as the crossover from the mean-field to the fluctuation-dominated regime highlight the role of the quasi-one-dimensional character in controlling the phase transition.
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Hwang J, Ruan W, Chen Y, Tang S, Crommie MF, Shen ZX, Mo SK. Charge density waves in two-dimensional transition metal dichalcogenides. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2024; 87:044502. [PMID: 38518359 DOI: 10.1088/1361-6633/ad36d3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 03/22/2024] [Indexed: 03/24/2024]
Abstract
Charge density wave (CDW is one of the most ubiquitous electronic orders in quantum materials. While the essential ingredients of CDW order have been extensively studied, a comprehensive microscopic understanding is yet to be reached. Recent research efforts on the CDW phenomena in two-dimensional (2D) materials provide a new pathway toward a deeper understanding of its complexity. This review provides an overview of the CDW orders in 2D with atomically thin transition metal dichalcogenides (TMDCs) as the materials platform. We mainly focus on the electronic structure investigations on the epitaxially grown TMDC samples with angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy as complementary experimental tools. We discuss the possible origins of the 2D CDW, novel quantum states coexisting with them, and exotic types of charge orders that can only be realized in the 2D limit.
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Affiliation(s)
- Jinwoong Hwang
- Department of Physics and Institute of Quantum Convergence Technology, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Wei Ruan
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, People's Republic of China
| | - Yi Chen
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, People's Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, People's Republic of China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, People's Republic of China
| | - Shujie Tang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, People's Republic of China
| | - Michael F Crommie
- Department of Physics, University of California, Berkeley, CA, United States of America
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States of America
- Kavli Energy NanoSciences Institute at the University of California at Berkeley, Berkeley, CA 94720, United States of America
| | - Zhi-Xun Shen
- Geballe Laboratory for Advanced Materials, Departments of Physics and Applied Physics, Stanford University, Stanford, CA, United States of America
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, United States of America
| | - Sung-Kwan Mo
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 United States of America
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6
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Knispel T, Berges J, Schobert A, van Loon EGCP, Jolie W, Wehling T, Michely T, Fischer J. Unconventional Charge-Density-Wave Gap in Monolayer NbS 2. NANO LETTERS 2024; 24:1045-1051. [PMID: 38232959 PMCID: PMC10835735 DOI: 10.1021/acs.nanolett.3c02787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Using scanning tunneling microscopy and spectroscopy, for a monolayer of transition metal dichalcogenide H-NbS2 grown by molecular beam epitaxy on graphene, we provide unambiguous evidence for a charge density wave (CDW) with a 3 × 3 superstructure, which is not present in bulk NbS2. Local spectroscopy displays a pronounced gap on the order of 20 meV at the Fermi level. Within the gap, low-energy features are present. The gap structure with its low-energy features is at variance with the expectation for a gap opening in the electronic band structure due to a CDW. Instead, comparison with ab initio calculations indicates that the observed gap structure must be attributed to combined electron-phonon quasiparticles. The phonons in question are the elusive amplitude and phase collective modes of the CDW transition. Our findings advance the understanding of CDW mechanisms in 2D materials and their spectroscopic signatures.
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Affiliation(s)
- Timo Knispel
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany
| | - Jan Berges
- U Bremen Excellence Chair, Bremen Center for Computational Materials Science, and MAPEX Center for Materials and Processes, University of Bremen, D-28359 Bremen, Germany
| | - Arne Schobert
- I. Institute of Theoretical Physics, Universität Hamburg, D-22607 Hamburg, Germany
| | - Erik G C P van Loon
- NanoLund and Division of Mathematical Physics, Department of Physics, Lund University, SE-22100 Lund, Sweden
| | - Wouter Jolie
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany
| | - Tim Wehling
- I. Institute of Theoretical Physics, Universität Hamburg, D-22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, D-22761 Hamburg, Germany
| | - Thomas Michely
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany
| | - Jeison Fischer
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany
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7
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Pouget JP, Canadell E. Structural approach to charge density waves in low-dimensional systems: electronic instability and chemical bonding. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2024; 87:026501. [PMID: 38052072 DOI: 10.1088/1361-6633/ad124f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 12/05/2023] [Indexed: 12/07/2023]
Abstract
The charge density wave (CDW) instability, usually occurring in low-dimensional metals, has been a topic of interest for longtime. However, some very fundamental aspects of the mechanism remain unclear. Recently, a plethora of new CDW materials, a substantial fraction of which is two-dimensional or even three-dimensional, has been prepared and characterised as bulk and/or single-layers. As a result, the need for revisiting the primary mechanism of the instability, based on the electron-hole instability established more than 50 years ago for quasi-one-dimensional (quasi-1D) conductors, has clearly emerged. In this work, we consider a large number of CDW materials to revisit the main concepts used in understanding the CDW instability, and emphasise the key role of the momentum dependent electron-phonon coupling in linking electronic and structural degrees of freedom. We argue that for quasi-1D systems, earlier weak coupling theories work appropriately and the energy gain due to the CDW and the concomitant periodic lattice distortion (PLD) remains primarily due to a Fermi surface nesting mechanism. However, for materials with higher dimensionality, intermediate and strong coupling regimes are generally at work and the modification of the chemical bonding network by the PLD is at the heart of the instability. We emphasise the need for a microscopic approach blending condensed matter physics concepts and state-of-the-art first-principles calculations with quite fundamental chemical bonding ideas in understanding the CDW phenomenon in these materials.
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Affiliation(s)
- Jean-Paul Pouget
- Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Enric Canadell
- Institut de Ciencia de Materials de Barcelona, ICMAB-CSIC, Campus de la UAB, 08193 Bellaterra, Spain, and Royal Academy of Sciences and Arts of Barcelona, Chemistry Section, La Rambla 115, 08002 Barcelona, Spain
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Du H, Jiang Z, Zheng J, Zhang X, Wang W, Zhang Z. Theoretical study of CDW phases for bulk NbX 2 (X = S and Se). Phys Chem Chem Phys 2024; 26:2376-2386. [PMID: 38167696 DOI: 10.1039/d3cp04426b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
In most two-dimensional transition metal chalcogenides, the superconducting phase coexists with the charge density wave (CDW) phase. There exists at least one case, i.e. bulk 2H-NbS2, that does not conform to this picture. Scientists have shown great interest in trying to experimentally find the CDW phase of bulk NbS2 since 1975. Is there any theoretically more stable thermodynamic state than its higher-temperature metal phase, especially in the case of charge injection? Theoretically more stable CDW bulk configurations (TC for 2H-NbS2 and TTs for 2H-NbSe2) with partial pseudo energy gaps were predicted through the harmonic phonon softening theory and first-principles calculations. The ratios of larger to smaller pseudo gaps around K-H segment in the Brillouin zone for CDW phases are basically equal to those of superconductivity phases for bulk 2H-NbX2 (X = S and Se). The CDW phase should coexist with its superconductor state below the critical temperature rather than the metal phase for bulk 2H-NbS2. The presence of CDW phase should be more easily observed experimentally when the injected charge reaches 0.5e/Nb18S36 for bulk 2H-NbS2. Our calculations of density of state (DOS) indicated that, during Nb atoms contracting to form the CDW phases with symmetry breaking in the in-plane direction, dominant conductive carriers are always of p-type for bulk 2H-NbS2 while the alternation of carrier type from p-type to n-type occurs for bulk 2H-NbSe2. The Fermi level continuously drops and then the M-L segment of the out-of-plane energy band emerges from the Fermi surface, which corresponds to the reversal of p-n type sign. Lifshitz transition of pocket-vanishing types occurs in the out-of-plane direction without symmetry breaking during the geometrical structural phase transition for bulk 2H-NbSe2. Our calculations have theoretically addressed the long-standing coexistence issue of CDW and superconducting phases.
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Affiliation(s)
- Hongwei Du
- Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Modern Physics, Northwest University, Xi'an 710069, China
| | - Zhenyi Jiang
- Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Modern Physics, Northwest University, Xi'an 710069, China
| | - Jiming Zheng
- Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Modern Physics, Northwest University, Xi'an 710069, China
| | - Xiaodong Zhang
- Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Modern Physics, Northwest University, Xi'an 710069, China
| | - Wenxuan Wang
- Shaanxi Key Laboratory for Theoretical Physics Frontiers, Institute of Modern Physics, Northwest University, Xi'an 710069, China
| | - Zhiyong Zhang
- Stanford Research Computing Center, Stanford University, Stanford, CA 94305, USA
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Cao S, Xu C, Fukui H, Manjo T, Dong Y, Shi M, Liu Y, Cao C, Song Y. Competing charge-density wave instabilities in the kagome metal ScV 6Sn 6. Nat Commun 2023; 14:7671. [PMID: 37996409 PMCID: PMC10667248 DOI: 10.1038/s41467-023-43454-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 11/09/2023] [Indexed: 11/25/2023] Open
Abstract
Owing to its unique geometry, the kagome lattice hosts various many-body quantum states including frustrated magnetism, superconductivity, and charge-density waves (CDWs). In this work, using inelastic X-ray scattering, we discover a dynamic short-range [Formula: see text] CDW that is dominant in the kagome metal ScV6Sn6 above TCDW ≈ 91 K, competing with the [Formula: see text] CDW that orders below TCDW. The competing CDW instabilities lead to an unusual CDW formation process, with the most pronounced phonon softening and the static CDW occurring at different wavevectors. First-principles calculations indicate that the [Formula: see text] CDW is energetically favored, while a wavevector-dependent electron-phonon coupling (EPC) promotes the [Formula: see text] CDW as the ground state, and leads to enhanced electron scattering above TCDW. These findings underscore EPC-driven correlated many-body physics in ScV6Sn6 and motivate studies of emergent quantum phases in the strong EPC regime.
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Affiliation(s)
- Saizheng Cao
- Center for Correlated Matter and School of Physics, Zhejiang University, 310058, Hangzhou, China
| | - Chenchao Xu
- School of Physics, Hangzhou Normal University, 310036, Hangzhou, China
| | - Hiroshi Fukui
- Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan
| | - Taishun Manjo
- Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan
| | - Ying Dong
- Research Center for Quantum Sensing, Zhejiang Lab, 310000, Hangzhou, P. R. China
| | - Ming Shi
- Center for Correlated Matter and School of Physics, Zhejiang University, 310058, Hangzhou, China
- Photon Science Division, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Yang Liu
- Center for Correlated Matter and School of Physics, Zhejiang University, 310058, Hangzhou, China
| | - Chao Cao
- Center for Correlated Matter and School of Physics, Zhejiang University, 310058, Hangzhou, China.
| | - Yu Song
- Center for Correlated Matter and School of Physics, Zhejiang University, 310058, Hangzhou, China.
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Liu J, Wu WF, Wang QW, Bai XC, Zeng Z, Zou LJ. Chiral charge density wave induced by mirror symmetry breaking in kagome metal. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 36:095601. [PMID: 37964592 DOI: 10.1088/1361-648x/ad0cae] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 11/14/2023] [Indexed: 11/16/2023]
Abstract
Kagome lattice provides a distinctive platform to investigate various correlated electron orders. Recently, an unconventional charge density wave (CDW) with novel chirality is observed in the kagome metalAV3Sb5(A= K, Rb, Cs), and the origin of which is still unclear. Here, using a tight-binding model and the mean-field method, we calculate the electron order in the quasi-two-dimensional kagome lattice with 1/3 electron filling, and show that the chiral CDW emerges under a set of parameters withC6rotational symmetry but without mirror symmetry. Physically, the reason why we choose this set of parameters is based on the possible tangential distortion of the kagome lattice. Our results provide a fresh insight to understand the microscopic origin of the unconventional CDW inAV3Sb5.
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Affiliation(s)
- Jing Liu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, PO Box 1129, Hefei 230031, People's Republic of China
| | - Wen-Feng Wu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, PO Box 1129, Hefei 230031, People's Republic of China
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Qing-Wei Wang
- School of Information Engineering, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, People's Republic of China
- Key Laboratory of Oceanographic Big Data Mining & Application of Zhejiang Province, Zhejiang Ocean University, Zhoushan, Zhejiang 316022, People's Republic of China
| | - Xiao-Cheng Bai
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, PO Box 1129, Hefei 230031, People's Republic of China
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Zhi Zeng
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, PO Box 1129, Hefei 230031, People's Republic of China
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Liang-Jian Zou
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, PO Box 1129, Hefei 230031, People's Republic of China
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, People's Republic of China
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11
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Shen X, Heid R, Hott R, Haghighirad AA, Salzmann B, Dos Reis Cantarino M, Monney C, Said AH, Frachet M, Murphy B, Rossnagel K, Rosenkranz S, Weber F. Precursor region with full phonon softening above the charge-density-wave phase transition in 2H-TaSe 2. Nat Commun 2023; 14:7282. [PMID: 37949889 PMCID: PMC10638379 DOI: 10.1038/s41467-023-43094-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
Research on charge-density-wave (CDW) ordered transition-metal dichalcogenides continues to unravel new states of quantum matter correlated to the intertwined lattice and electronic degrees of freedom. Here, we report an inelastic x-ray scattering investigation of the lattice dynamics of the canonical CDW compound 2H-TaSe2 complemented by angle-resolved photoemission spectroscopy and density functional perturbation theory. Our results rule out the formation of a central-peak without full phonon softening for the CDW transition in 2H-TaSe2 and provide evidence for a novel precursor region above the CDW transition temperature TCDW, which is characterized by an overdamped phonon mode and not detectable in our photoemission experiments. Thus, 2H-TaSe2 exhibits structural before electronic static order and emphasizes the important lattice contribution to CDW transitions. Our ab-initio calculations explain the interplay of electron-phonon coupling and Fermi surface topology triggering the CDW phase transition and predict that the CDW soft phonon mode promotes emergent superconductivity near the pressure-driven CDW quantum critical point.
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Affiliation(s)
- Xingchen Shen
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
- College of Physics, Chongqing University, Chongqing, 401331, P. R. China
| | - Rolf Heid
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Roland Hott
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Amir-Abbas Haghighirad
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Björn Salzmann
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Marli Dos Reis Cantarino
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
- Instituto de Física, Universidade de São Paulo, São Paulo, São Paulo, 05508-090, Brazil
| | - Claude Monney
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Ayman H Said
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Mehdi Frachet
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Bridget Murphy
- Institute of Experimental and Applied Physics and KiNSIS, Kiel University, 24098, Kiel, Germany
- Ruprecht Haensel Laboratory, Kiel University, 24098, Kiel, Germany
| | - Kai Rossnagel
- Institute of Experimental and Applied Physics and KiNSIS, Kiel University, 24098, Kiel, Germany
- Ruprecht Haensel Laboratory, Kiel University, 24098, Kiel, Germany
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607, Hamburg, Germany
| | - Stephan Rosenkranz
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Frank Weber
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany.
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12
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Wu S, Basak R, Li W, Kim JW, Ryan PJ, Lu D, Hashimoto M, Nelson C, Acevedo-Esteves R, Haley SC, Analytis JG, He Y, Frano A, Birgeneau RJ. Discovery of Charge Order in the Transition Metal Dichalcogenide Fe_{x}NbS_{2}. PHYSICAL REVIEW LETTERS 2023; 131:186701. [PMID: 37977621 DOI: 10.1103/physrevlett.131.186701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 09/08/2023] [Indexed: 11/19/2023]
Abstract
The Fe intercalated transition metal dichalcogenide (TMD), Fe_{1/3}NbS_{2}, exhibits remarkable resistance switching properties and highly tunable spin ordering phases due to magnetic defects. We conduct synchrotron x-ray scattering measurements on both underintercalated (x=0.32) and overintercalated (x=0.35) samples. We discover a new charge order phase in the overintercalated sample, where the excess Fe atoms lead to a zigzag antiferromagnetic order. The agreement between the charge and magnetic ordering temperatures, as well as their intensity relationship, suggests a strong magnetoelastic coupling as the mechanism for the charge ordering. Our results reveal the first example of a charge order phase among the intercalated TMD family and demonstrate the ability to stabilize charge modulation by introducing electronic correlations, where the charge order is absent in bulk 2H-NbS_{2} compared to other pristine TMDs.
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Affiliation(s)
- Shan Wu
- Department of Physics, University of California Berkeley, California 94720, USA
- Material Sciences Division, Lawrence Berkeley National Lab, Berkeley, California 94720, USA
- Department of Physics, Santa Clara University, Santa Clara, California 95053, USA
| | - Rourav Basak
- Department of Physics, University of California San Diego, San Diego, California 92093, USA
| | - Wenxin Li
- Department of Applied Physics, Yale University, New Haven, Connecticut 06511, USA
| | - Jong-Woo Kim
- Advanced Photon Source, Argonne National Laboratories, Lemont, Illinois, USA
| | - Philip J Ryan
- Advanced Photon Source, Argonne National Laboratories, Lemont, Illinois, USA
| | - Donghui Lu
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Makoto Hashimoto
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Christie Nelson
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Raul Acevedo-Esteves
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Shannon C Haley
- Department of Physics, University of California Berkeley, California 94720, USA
| | - James G Analytis
- Department of Physics, University of California Berkeley, California 94720, USA
- CIFAR Quantum Materials, CIFAR, Toronto, Ontario M5G 1M1, Canada
| | - Yu He
- Department of Applied Physics, Yale University, New Haven, Connecticut 06511, USA
| | - Alex Frano
- Department of Physics, University of California San Diego, San Diego, California 92093, USA
| | - Robert J Birgeneau
- Department of Physics, University of California Berkeley, California 94720, USA
- Material Sciences Division, Lawrence Berkeley National Lab, Berkeley, California 94720, USA
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13
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Korshunov A, Hu H, Subires D, Jiang Y, Călugăru D, Feng X, Rajapitamahuni A, Yi C, Roychowdhury S, Vergniory MG, Strempfer J, Shekhar C, Vescovo E, Chernyshov D, Said AH, Bosak A, Felser C, Bernevig BA, Blanco-Canosa S. Softening of a flat phonon mode in the kagome ScV 6Sn 6. Nat Commun 2023; 14:6646. [PMID: 37863907 PMCID: PMC10589229 DOI: 10.1038/s41467-023-42186-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/29/2023] [Indexed: 10/22/2023] Open
Abstract
Geometrically frustrated kagome lattices are raising as novel platforms to engineer correlated topological electron flat bands that are prominent to electronic instabilities. Here, we demonstrate a phonon softening at the kz = π plane in ScV6Sn6. The low energy longitudinal phonon collapses at ~98 K and q = [Formula: see text] due to the electron-phonon interaction, without the emergence of long-range charge order which sets in at a different propagation vector qCDW = [Formula: see text]. Theoretical calculations corroborate the experimental finding to indicate that the leading instability is located at [Formula: see text] of a rather flat mode. We relate the phonon renormalization to the orbital-resolved susceptibility of the trigonal Sn atoms and explain the approximately flat phonon dispersion. Our data report the first example of the collapse of a kagome bosonic mode and promote the 166 compounds of kagomes as primary candidates to explore correlated flat phonon-topological flat electron physics.
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Affiliation(s)
- A Korshunov
- European Synchrotron Radiation Facility (ESRF), BP 220, F-38043, Grenoble, France
| | - H Hu
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, 20018, San Sebastián, Spain
| | - D Subires
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, 20018, San Sebastián, Spain
| | - Y Jiang
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - D Călugăru
- Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - X Feng
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, 20018, San Sebastián, Spain
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - A Rajapitamahuni
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - C Yi
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - S Roychowdhury
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - M G Vergniory
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, 20018, San Sebastián, Spain
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - J Strempfer
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - C Shekhar
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - E Vescovo
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - D Chernyshov
- Swiss-Norwegian BeamLines at European Synchrotron Radiation Facility, Grenoble, France
| | - A H Said
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - A Bosak
- European Synchrotron Radiation Facility (ESRF), BP 220, F-38043, Grenoble, France
| | - C Felser
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - B Andrei Bernevig
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, 20018, San Sebastián, Spain.
- Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
- IKERBASQUE, Basque Foundation for Science, 48013, Bilbao, Spain.
| | - S Blanco-Canosa
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, 20018, San Sebastián, Spain.
- IKERBASQUE, Basque Foundation for Science, 48013, Bilbao, Spain.
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14
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Miao H, Zhang TT, Li HX, Fabbris G, Said AH, Tartaglia R, Yilmaz T, Vescovo E, Yin JX, Murakami S, Feng XL, Jiang K, Wu XL, Wang AF, Okamoto S, Wang YL, Lee HN. Signature of spin-phonon coupling driven charge density wave in a kagome magnet. Nat Commun 2023; 14:6183. [PMID: 37793998 PMCID: PMC10550957 DOI: 10.1038/s41467-023-41957-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/21/2023] [Indexed: 10/06/2023] Open
Abstract
The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2[Formula: see text]2[Formula: see text]1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe.
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Affiliation(s)
- H Miao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - T T Zhang
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
| | - H X Li
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Advanced Materials Thrust, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China
| | - G Fabbris
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - A H Said
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - R Tartaglia
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
- "Gleb Wataghin" Institute of Physics, University of Campinas, Campinas, São Paulo, Brazil
| | - T Yilmaz
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, USA
| | - E Vescovo
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, USA
| | - J-X Yin
- Laboratory for Quantum Emergence, Department of Physics, Southern University of Science and Technology, Shenzhen, China
| | - S Murakami
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
| | - X L Feng
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - K Jiang
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - X L Wu
- Low Temperature Physics Laboratory, College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing, China
| | - A F Wang
- Low Temperature Physics Laboratory, College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing, China.
| | - S Okamoto
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - Y L Wang
- School of Emerging Technology, University of Science and Technology of China, Hefei, Anhui, China.
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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15
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Chen H, Yang YF, Zhang GM, Liu H. An electronic origin of charge order in infinite-layer nickelates. Nat Commun 2023; 14:5477. [PMID: 37673936 PMCID: PMC10482875 DOI: 10.1038/s41467-023-41236-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 08/23/2023] [Indexed: 09/08/2023] Open
Abstract
A charge order (CO) with a wavevector [Formula: see text] is observed in infinite-layer nickelates. Here we use first-principles calculations to demonstrate a charge-transfer-driven CO mechanism in infinite-layer nickelates, which leads to a characteristic Ni1+-Ni2+-Ni1+ stripe state. For every three Ni atoms, due to the presence of near-Fermi-level conduction bands, Hubbard interaction on Ni-d orbitals transfers electrons on one Ni atom to conduction bands and leaves electrons on the other two Ni atoms to become more localized. We further derive a low-energy effective model to elucidate that the CO state arises from a delicate competition between Hubbard interaction on Ni-d orbitals and charge transfer energy between Ni-d orbitals and conduction bands. With physically reasonable parameters, [Formula: see text] CO state is more stable than uniform paramagnetic state and usual checkerboard antiferromagnetic state. Our work highlights the multi-band nature of infinite-layer nickelates, which leads to some distinctive correlated properties that are not found in cuprates.
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Affiliation(s)
- Hanghui Chen
- NYU-ECNU Institute of Physics, NYU Shanghai, Shanghai, 200122, China.
- Department of Physics, New York University, New York, NY, 10012, USA.
| | - Yi-Feng Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- University of Chinese Academy of Sciences, Beijing, 100190, China.
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
| | - Guang-Ming Zhang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China.
- Frontier Science Center for Quantum Information, Beijing, 100084, China.
| | - Hongquan Liu
- NYU-ECNU Institute of Physics, NYU Shanghai, Shanghai, 200122, China
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16
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Xu L, Wu J, Liu Z, Kong W, Wang C, Zhang Y, Tan S. Influence of the physical properties of the layered oxyselenides Bi 2YO 4Cu 2Se 2 through Ni doping. RSC Adv 2023; 13:18812-18815. [PMID: 37346940 PMCID: PMC10281491 DOI: 10.1039/d3ra03136e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 06/14/2023] [Indexed: 06/23/2023] Open
Abstract
We have synthesized a series of Ni-doped layered oxyselenides Bi2YO4Cu2-xNixSe2 (0 ≤ x ≤ 0.4). The crystal structure and physical properties were studied through X-ray diffraction, and electric and thermo transport measurements. We also performed DFT calculations to study the electric structure of the designed Bi2YO4Ni2Se2, which is similar to that of KNi2Se2.
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Affiliation(s)
- Lin Xu
- Yantai Gold College Yantai 265401 People's Republic of China
| | - Jingyuan Wu
- Longkou No. 1 High School of Shandong Province Yantai 265401 People's Republic of China
| | - Zhidong Liu
- School of Physics and Optoelectronic Engineering, Shandong University of Technology Zibo 255000 People's Republic of China
| | - Weiao Kong
- School of Physics and Optoelectronic Engineering, Shandong University of Technology Zibo 255000 People's Republic of China
| | - Chuanhe Wang
- School of Physics and Optoelectronic Engineering, Shandong University of Technology Zibo 255000 People's Republic of China
| | - Yani Zhang
- School of Physics and Optoelectronic Engineering, Shandong University of Technology Zibo 255000 People's Republic of China
| | - Shugang Tan
- School of Physics and Optoelectronic Engineering, Shandong University of Technology Zibo 255000 People's Republic of China
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17
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Shao S, Yin JX, Belopolski I, You JY, Hou T, Chen H, Jiang Y, Hossain MS, Yahyavi M, Hsu CH, Feng YP, Bansil A, Hasan MZ, Chang G. Intertwining of Magnetism and Charge Ordering in Kagome FeGe. ACS NANO 2023. [PMID: 37186957 DOI: 10.1021/acsnano.3c00229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Recent experiments report a charge density wave (CDW) in the antiferromagnet FeGe, but the nature of the charge ordering and the associated structural distortion remains elusive. We discuss the structural and electronic properties of FeGe. Our proposed ground state phase accurately captures atomic topographies acquired by scanning tunneling microscopy. We show that the 2 × 2 × 1 CDW likely results from the Fermi surface nesting of hexagonal-prism-shaped kagome states. FeGe is found to exhibit distortions in the positions of the Ge atoms instead of the Fe atoms in the kagome layers. Using in-depth first-principles calculations and analytical modeling, we demonstrate that this unconventional distortion is driven by the intertwining of magnetic exchange coupling and CDW interactions in this kagome material. The movement of Ge atoms from their pristine positions also enhances the magnetic moment of the Fe kagome layers. Our study indicates that magnetic kagome lattices provide a material candidate for exploring the effects of strong electronic correlations on the ground state and their implications for transport, magnetic, and optical responses in materials.
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Affiliation(s)
- Sen Shao
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Jia-Xin Yin
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Ilya Belopolski
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan
| | - Jing-Yang You
- Department of Physics, National University of Singapore, 2 Science Drive 3, 117551 Singapore
| | - Tao Hou
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Hongyu Chen
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Yuxiao Jiang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, New Jersey 08544, United States
| | - Md Shafayat Hossain
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, New Jersey 08544, United States
| | - Mohammad Yahyavi
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Chia-Hsiu Hsu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Yuan Ping Feng
- Department of Physics, National University of Singapore, 2 Science Drive 3, 117551 Singapore
| | - Arun Bansil
- Department of Physics, Northeastern University, Boston, Massachusetts 02115, United States
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, New Jersey 08544, United States
| | - Guoqing Chang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
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18
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Jiang C, Beneduce E, Baggioli M, Setty C, Zaccone A. Possible enhancement of the superconductingTcdue to sharp Kohn-like soft phonon anomalies. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:164003. [PMID: 36808073 DOI: 10.1088/1361-648x/acbd0a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Phonon softening is a ubiquitous phenomenon in condensed matter systems which is often associated with charge density wave (CDW) instabilities and anharmonicity. The interplay between phonon softening, CDW and superconductivity is a topic of intense debate. In this work, the effects of anomalous soft phonon instabilities on superconductivity are studied based on a recently developed theoretical framework that accounts for phonon damping and softening within the Migdal-Eliashberg theory. Model calculations show that the phonon softening in the form of a sharp dip in the phonon dispersion relation, either acoustic or optical (including the case of Kohn-type anomalies typically associated with CDW), can cause a manifold increase of the electron-phonon coupling constantλ. This, under certain conditions, which are consistent with the concept of optimal frequency introduced by Bergmann and Rainer, can produce a large increase of the superconducting transition temperatureTc. In summary, our results suggest the possibility of reaching high-temperature superconductivity by exploiting soft phonon anomalies restricted in momentum space.
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Affiliation(s)
- Cunyuan Jiang
- School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Enrico Beneduce
- Department of Physics "A. Pontremoli", University of Milan, via Celoria 16, 20133 Milan, Italy
| | - Matteo Baggioli
- School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
- Wilczek Quantum Center, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
- Shanghai Research Center for Quantum Sciences, Shanghai 201315, People's Republic of China
| | - Chandan Setty
- Department of Physics and Astronomy, Rice Center for Quantum Materials, Rice University, Houston, TX 77005, United States of America
| | - Alessio Zaccone
- Department of Physics "A. Pontremoli", University of Milan, via Celoria 16, 20133 Milan, Italy
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19
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Li YX, Yao ZJ, Yu SL, Li JX. Superconductivity and density-wave fluctuations in an extended triangular Hubbard model: an application to SnSe 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 35:045602. [PMID: 36541553 DOI: 10.1088/1361-648x/aca85e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
We employ the fluctuation-exchange approximation to study the relation of superconducting pairing symmetries and density-wave fluctuations based on the extended triangular Hubbard model upon electron doping and interactions, with an possible application to the layered metal dichalcogenide SnSe2. For the case where the interactions between electrons contain only the on-site Hubbard term, the superconducting pairings are mainly mediated by spin fluctuations, and the spin-singlet pairing with thed-wave symmetry robustly dominates in the low and moderate doping levels, and ad-wave to extendeds-wave transition is observed as the electron doping reachesn = 1. When the near-neighbor site Coulomb interactions are also included, the charge fluctuations are enhanced, and the spin-triplet pairings with thep-wave andf-wave symmetries can be realized in the high and low doping levels, respectively.
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Affiliation(s)
- Yun-Xiao Li
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
| | - Zi-Jian Yao
- Department of Physics, Nanjing Normal University, Nanjing 210023, People's Republic of China
| | - Shun-Li Yu
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China
| | - Jian-Xin Li
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China
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20
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Souliou SM, Lacmann T, Heid R, Meingast C, Frachet M, Paolasini L, Haghighirad AA, Merz M, Bosak A, Le Tacon M. Soft-Phonon and Charge-Density-Wave Formation in Nematic BaNi_{2}As_{2}. PHYSICAL REVIEW LETTERS 2022; 129:247602. [PMID: 36563274 DOI: 10.1103/physrevlett.129.247602] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/14/2022] [Accepted: 11/21/2022] [Indexed: 06/17/2023]
Abstract
We use diffuse and inelastic x-ray scattering to study the formation of an incommensurate charge-density-wave (I-CDW) in BaNi_{2}As_{2}, a candidate system for charge-driven electronic nematicity. Intense diffuse scattering is observed around the modulation vector of the I-CDW, Q_{I-CDW}. It is already visible at room temperature and collapses into superstructure reflections in the long-range ordered state where a small orthorhombic distortion occurs. A clear dip in the dispersion of a low-energy transverse optical phonon mode is observed around Q_{I-CDW}. The phonon continuously softens upon cooling, ultimately driving the transition to the I-CDW state. The transverse character of the soft-phonon branch elucidates the complex pattern of the I-CDW satellites observed in the current and earlier studies and settles the debated unidirectional nature of the I-CDW. The phonon instability and its reciprocal space position are well captured by our ab initio calculations. These, however, indicate that neither Fermi surface nesting, nor enhanced momentum-dependent electron-phonon coupling can account for the I-CDW formation, demonstrating its unconventional nature.
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Affiliation(s)
- S M Souliou
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
| | - T Lacmann
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
| | - R Heid
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
| | - C Meingast
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
| | - M Frachet
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
| | - L Paolasini
- ESRF The European Synchrotron, 71 avenue des Martyrs, CS 40220 F-38043 Grenoble, Cedex 9, France
| | - A-A Haghighirad
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
| | - M Merz
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
- Karlsruhe Nano Micro Facility (KNMFi), Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - A Bosak
- ESRF The European Synchrotron, 71 avenue des Martyrs, CS 40220 F-38043 Grenoble, Cedex 9, France
| | - M Le Tacon
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76021 Karlsruhe, Germany
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21
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Observation of anomalous amplitude modes in the kagome metal CsV 3Sb 5. Nat Commun 2022; 13:3461. [PMID: 35710635 PMCID: PMC9203454 DOI: 10.1038/s41467-022-31162-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 06/03/2022] [Indexed: 11/09/2022] Open
Abstract
The kagome lattice provides a fertile platform to explore novel symmetry-breaking states. Charge-density wave (CDW) instabilities have been recently discovered in a new kagome metal family, commonly considered to arise from Fermi-surface instabilities. Here we report the observation of Raman-active CDW amplitude modes in CsV3Sb5, which are collective excitations typically thought to emerge out of frozen soft phonons, although phonon softening is elusive experimentally. The amplitude modes strongly hybridize with other superlattice modes, imparting them with clear temperature-dependent frequency shift and broadening, rarely seen in other known CDW materials. Both the mode mixing and the large amplitude mode frequencies suggest that the CDW exhibits the character of strong electron-phonon coupling, a regime in which phonon softening can cease to exist. Our work highlights the importance of the lattice degree of freedom in the CDW formation and points to the complex nature of the mechanism. The mechanism of the charge density wave in kagome metals is not fully understood. Here, the authors report the observation of unusual large-frequency collective lattice excitations, or amplitude modes, in CsV3Sb5 in the absence of phonon mode softening, evidencing the strong electron-phonon coupling regime.
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22
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Qu AC, Nigge P, Link S, Levy G, Michiardi M, Spandar PL, Matthé T, Schneider M, Zhdanovich S, Starke U, Gutiérrez C, Damascelli A. Ubiquitous defect-induced density wave instability in monolayer graphene. SCIENCE ADVANCES 2022; 8:eabm5180. [PMID: 35675409 PMCID: PMC9177069 DOI: 10.1126/sciadv.abm5180] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 04/20/2022] [Indexed: 06/15/2023]
Abstract
Quantum materials are notoriously sensitive to their environments, where small perturbations can tip a system toward one of several competing ground states. Graphene hosts a rich assortment of such competing phases, including a bond density wave instability ("Kekulé distortion") that couples electrons at the K/K' valleys and breaks the lattice symmetry. Here, we report observations of a ubiquitous Kekulé distortion across multiple graphene systems. We show that extremely dilute concentrations of surface atoms (less than three adsorbed atoms every 1000 graphene unit cells) can self-assemble and trigger the onset of a global Kekulé density wave phase. Combining complementary momentum-sensitive angle-resolved photoemission spectroscopy (ARPES) and low-energy electron diffraction (LEED) measurements, we confirm the presence of this density wave phase and observe the opening of an energy gap. Our results reveal an unexpected sensitivity of the graphene lattice to dilute surface disorder and show that adsorbed atoms offer an attractive route toward designing novel phases in two-dimensional materials.
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Affiliation(s)
- A. C. Qu
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
| | - P. Nigge
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
| | - S. Link
- Max Planck Institute for Solid State Research, Stuttgart, Germany
| | - G. Levy
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
| | - M. Michiardi
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - P. L. Spandar
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA, USA
| | - T. Matthé
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
| | - M. Schneider
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
| | - S. Zhdanovich
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
| | - U. Starke
- Max Planck Institute for Solid State Research, Stuttgart, Germany
| | - C. Gutiérrez
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA, USA
| | - A. Damascelli
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, Canada
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23
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Chowdhury S, Rigosi AF, Hill HM, Briggs A, Newell DB, Berger H, Hight Walker AR, Tavazza F. Influence of Dimensionality on the Charge Density Wave Phase of 2H‐TaSe
2. ADVANCED THEORY AND SIMULATIONS 2022. [DOI: 10.1002/adts.202100329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sugata Chowdhury
- Department of Physics and Astronomy Howard University Washington DC 20059 USA
| | - Albert F. Rigosi
- National Institute of Standards and Technology Gaithersburg MD 20899 USA
| | - Heather M. Hill
- National Institute of Standards and Technology Gaithersburg MD 20899 USA
| | - Andrew Briggs
- National Institute of Standards and Technology Gaithersburg MD 20899 USA
| | - David B. Newell
- National Institute of Standards and Technology Gaithersburg MD 20899 USA
| | - Helmuth Berger
- École Polytechnique Fédérale de Lausanne (EPFL) Institut de Physique des Nanostructures Lausanne CH‐1015 Switzerland
| | | | - Francesca Tavazza
- National Institute of Standards and Technology Gaithersburg MD 20899 USA
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24
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Zheng Y, Jiang X, Xue XX, Yao X, Zeng J, Chen KQ, Wang E, Feng Y. Nuclear Quantum Effects on the Charge-Density Wave Transition in NbX 2 (X = S, Se). NANO LETTERS 2022; 22:1858-1865. [PMID: 35174707 DOI: 10.1021/acs.nanolett.1c04015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Understanding the origin of charge-density wave (CDW) instability is important for manipulating novel collective electronic states. Many layered transition metal dichalcogenides (TMDs) share similarity in the structural and electronic instability, giving rise to diverse CDW phases and superconductivity. It is still puzzling that even isostructural and isoelectronic TMDs show distinct CDW features. For instance, bulk NbSe2 exhibits CDW order at low temperature, while bulk NbS2 displays no CDW instability. The CDW transitions in single-layer NbS2 and NbSe2 are also different. In the classic limit, we investigate the electron correlation effects on the dimensionality dependence of the CDW ordering. By performing ab initio path integral molecular dynamics simulations and comparative analyses, we further revealed significant nuclear quantum effects in these systems. Specifically, the quantum motion of sulfur anions significantly reduces the CDW transition temperature in both bulk and single-layer NbS2, resulting in distinct CDW features in the NbS2 and NbSe2 systems.
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Affiliation(s)
- Yueshao Zheng
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
| | - Xingxing Jiang
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
| | - Xiong-Xiong Xue
- School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Xiaolong Yao
- School of Physics and Technology, Xinjiang University, Urumqi 830046, People's Republic of China
| | - Jiang Zeng
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
| | - Ke-Qiu Chen
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
| | - Enge Wang
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, People's Republic of China
- Songshan Lake Materials, Institute of Physics, CAS and School of Physics, Liaoning University, Shenyang 110036, People's Republic of China
| | - Yexin Feng
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
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25
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Ganguli SC, Vaňo V, Kezilebieke S, Lado JL, Liljeroth P. Confinement-Engineered Superconductor to Correlated-Insulator Transition in a van der Waals Monolayer. NANO LETTERS 2022; 22:1845-1850. [PMID: 35167310 PMCID: PMC8915256 DOI: 10.1021/acs.nanolett.1c03491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 02/10/2022] [Indexed: 06/14/2023]
Abstract
Transition metal dichalcogenides (TMDC) are a rich family of two-dimensional materials displaying a multitude of different quantum ground states. In particular, d3 TMDCs are paradigmatic materials hosting a variety of symmetry broken states, including charge density waves, superconductivity, and magnetism. Among this family, NbSe2 is one of the best-studied superconducting materials down to the monolayer limit. Despite its superconducting nature, a variety of results point toward strong electronic repulsions in NbSe2. Here, we control the strength of the interactions experimentally via quantum confinement and use low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) to demonstrate that NbSe2 is in close proximity to a correlated insulating state. This reveals the coexistence of competing interactions in NbSe2, creating a transition from a superconducting to an insulating quantum correlated state by confinement-controlled interactions. Our results demonstrate the dramatic role of interactions in NbSe2, establishing NbSe2 as a correlated superconductor with competing interactions.
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Affiliation(s)
| | - Viliam Vaňo
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | | | - Jose L. Lado
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
| | - Peter Liljeroth
- Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland
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26
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Chowdhury S, Rigosi AF, Hill HM, Vora P, Hight Walker AR, Tavazza F. Computational Methods for Charge Density Waves in 2D Materials. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:504. [PMID: 35159849 PMCID: PMC8839743 DOI: 10.3390/nano12030504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/20/2022] [Accepted: 01/26/2022] [Indexed: 11/29/2022]
Abstract
Two-dimensional (2D) materials that exhibit charge density waves (CDWs)-spontaneous reorganization of their electrons into a periodic modulation-have generated many research endeavors in the hopes of employing their exotic properties for various quantum-based technologies. Early investigations surrounding CDWs were mostly focused on bulk materials. However, applications for quantum devices require few-layer materials to fully utilize the emergent phenomena. The CDW field has greatly expanded over the decades, warranting a focus on the computational efforts surrounding them specifically in 2D materials. In this review, we cover ground in the following relevant theory-driven subtopics for TaS2 and TaSe2: summary of general computational techniques and methods, resulting atomic structures, the effect of electron-phonon interaction of the Raman scattering modes, the effects of confinement and dimensionality on the CDW, and we end with a future outlook. Through understanding how the computational methods have enabled incredible advancements in quantum materials, one may anticipate the ever-expanding directions available for continued pursuit as the field brings us through the 21st century.
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Affiliation(s)
- Sugata Chowdhury
- Department of Physics and Astronomy, Howard University, Washington, DC 20059, USA;
- Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA
| | - Albert F. Rigosi
- Physical Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA; (A.F.R.); (H.M.H.); (A.R.H.W.)
| | - Heather M. Hill
- Physical Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA; (A.F.R.); (H.M.H.); (A.R.H.W.)
- Physics Today, American Institute of Physics, College Park, MD 20740, USA
| | - Patrick Vora
- Quantum Science and Engineering Center, George Mason University, Fairfax, VA 22030, USA;
- Department of Physics and Astronomy, George Mason University, Fairfax, VA 22030, USA
| | - Angela R. Hight Walker
- Physical Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA; (A.F.R.); (H.M.H.); (A.R.H.W.)
| | - Francesca Tavazza
- Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA
- Physical Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA; (A.F.R.); (H.M.H.); (A.R.H.W.)
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27
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Kurzhals P, Kremer G, Jaouen T, Nicholson CW, Heid R, Nagel P, Castellan JP, Ivanov A, Muntwiler M, Rumo M, Salzmann B, Strocov VN, Reznik D, Monney C, Weber F. Electron-momentum dependence of electron-phonon coupling underlies dramatic phonon renormalization in YNi 2B 2C. Nat Commun 2022; 13:228. [PMID: 35017477 PMCID: PMC8752669 DOI: 10.1038/s41467-021-27843-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 12/16/2021] [Indexed: 11/09/2022] Open
Abstract
Electron-phonon coupling, i.e., the scattering of lattice vibrations by electrons and vice versa, is ubiquitous in solids and can lead to emergent ground states such as superconductivity and charge-density wave order. A broad spectral phonon line shape is often interpreted as a marker of strong electron-phonon coupling associated with Fermi surface nesting, i.e., parallel sections of the Fermi surface connected by the phonon momentum. Alternatively broad phonons are known to arise from strong atomic lattice anharmonicity. Here, we show that strong phonon broadening can occur in the absence of both Fermi surface nesting and lattice anharmonicity, if electron-phonon coupling is strongly enhanced for specific values of electron-momentum, k. We use inelastic neutron scattering, soft x-ray angle-resolved photoemission spectroscopy measurements and ab-initio lattice dynamical and electronic band structure calculations to demonstrate this scenario in the highly anisotropic tetragonal electron-phonon superconductor YNi2B2C. This new scenario likely applies to a wide range of compounds.
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Affiliation(s)
- Philipp Kurzhals
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Geoffroy Kremer
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Thomas Jaouen
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251, F-35000, Rennes, France
| | - Christopher W Nicholson
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Rolf Heid
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Peter Nagel
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - John-Paul Castellan
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
- Laboratoire Léon Brillouin (CEA-CNRS), CEA Saclay, F-91911, Gif-sur-Yvette, France
| | - Alexandre Ivanov
- Institut Laue-Langevin, 71 avenue des Martyrs CS 20156, 38042, Grenoble Cedex 9, France
| | - Matthias Muntwiler
- Paul Scherrer Institut, Swiss Light Source, 5232, Villigen PSI, Switzerland
| | - Maxime Rumo
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Bjoern Salzmann
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Vladimir N Strocov
- Paul Scherrer Institut, Swiss Light Source, 5232, Villigen PSI, Switzerland
| | - Dmitry Reznik
- Department of Physics, University of Colorado at Boulder, Boulder, CO, 80309, USA
- Center for Experiments on Quantum Materials, University of Colorado at Boulder, Boulder, CO, 80309, USA
| | - Claude Monney
- Département de Physique and Fribourg Center for Nanomaterials, Université de Fribourg, 1700, Fribourg, Switzerland
| | - Frank Weber
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany.
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28
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Trzaskowska A, Mielcarek S, Wiesner M, Lombardi F, Mroz B. Dispersion of the surface phonons in semiconductor/topological insulator Si/Bi 2Te 3 heterostructure studied by high resolution Brillouin spectroscopy. ULTRASONICS 2021; 117:106526. [PMID: 34303926 DOI: 10.1016/j.ultras.2021.106526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/11/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
The dynamics and dispersion of surface phonons in heterostructure semiconductor/ topological insulator Si/Bi2Te3 was investigated using high resolution Brillouin light scattering method in the GHz frequency range. Both Rayleigh and Sezawa surface acoustic waves have been observed for wave vectors ranging from 0.006 to 0.023 nm-1. Anomaly in dispersion relations ω(q) for both surface waves were detected for the wave vector q = 0.016 nm-1. The finite element method (FEM) was used to simulate the observed shapes of ω(q) and to find the deformation profiles of surface acoustic waves. We attribute the observed changes to the coupling between low energy electrons and surface phonons. The coupling between helical Dirac states and surface phonons is discussed in the frame of accessible theoretical models.
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Affiliation(s)
- A Trzaskowska
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznan, Poland.
| | - S Mielcarek
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznan, Poland
| | - M Wiesner
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznan, Poland
| | - F Lombardi
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-412 96, Göteborg, Sweden
| | - B Mroz
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznan, Poland
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29
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van Efferen C, Berges J, Hall J, van Loon E, Kraus S, Schobert A, Wekking T, Huttmann F, Plaar E, Rothenbach N, Ollefs K, Arruda LM, Brookes N, Schönhoff G, Kummer K, Wende H, Wehling T, Michely T. A full gap above the Fermi level: the charge density wave of monolayer VS 2. Nat Commun 2021; 12:6837. [PMID: 34824213 PMCID: PMC8617271 DOI: 10.1038/s41467-021-27094-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 11/04/2021] [Indexed: 11/09/2022] Open
Abstract
In the standard model of charge density wave (CDW) transitions, the displacement along a single phonon mode lowers the total electronic energy by creating a gap at the Fermi level, making the CDW a metal-insulator transition. Here, using scanning tunneling microscopy and spectroscopy and ab initio calculations, we show that VS2 realizes a CDW which stands out of this standard model. There is a full CDW gap residing in the unoccupied states of monolayer VS2. At the Fermi level, the CDW induces a topological metal-metal (Lifshitz) transition. Non-linear coupling of transverse and longitudinal phonons is essential for the formation of the CDW and the full gap above the Fermi level. Additionally, x-ray magnetic circular dichroism reveals the absence of net magnetization in this phase, pointing to coexisting charge and spin density waves in the ground state.
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Affiliation(s)
- Camiel van Efferen
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany.
| | - Jan Berges
- Institut für Theoretische Physik, Bremen Center for Computational Materials Science, and MAPEX Center for Materials and Processes, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
| | - Joshua Hall
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
| | - Erik van Loon
- Institut für Theoretische Physik, Bremen Center for Computational Materials Science, and MAPEX Center for Materials and Processes, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
| | - Stefan Kraus
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
| | - Arne Schobert
- Institut für Theoretische Physik, Bremen Center for Computational Materials Science, and MAPEX Center for Materials and Processes, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
| | - Tobias Wekking
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
| | - Felix Huttmann
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
| | - Eline Plaar
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
| | - Nico Rothenbach
- Fakultät für Physik und Center für Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, Carl-Benz-Straße, 47057, Duisburg, Germany
| | - Katharina Ollefs
- Fakultät für Physik und Center für Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, Carl-Benz-Straße, 47057, Duisburg, Germany
| | - Lucas Machado Arruda
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
| | - Nick Brookes
- European Synchrotron Research Facility (ESRF), Avenue des Martyrs 71, CS 40220, 38043, Grenoble Cedex 9, France
| | - Gunnar Schönhoff
- Institut für Theoretische Physik, Bremen Center for Computational Materials Science, and MAPEX Center for Materials and Processes, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
| | - Kurt Kummer
- European Synchrotron Research Facility (ESRF), Avenue des Martyrs 71, CS 40220, 38043, Grenoble Cedex 9, France
| | - Heiko Wende
- Fakultät für Physik und Center für Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, Carl-Benz-Straße, 47057, Duisburg, Germany
| | - Tim Wehling
- Institut für Theoretische Physik, Bremen Center for Computational Materials Science, and MAPEX Center for Materials and Processes, Universität Bremen, Otto-Hahn-Allee 1, 28359, Bremen, Germany
- Institute of Theoretical Physics, Universität Hamburg, Notkestraße 9-11, 22607, Hamburg, Germany
| | - Thomas Michely
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
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30
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Zong A, Dolgirev PE, Kogar A, Su Y, Shen X, Straquadine JAW, Wang X, Luo D, Kozina ME, Reid AH, Li R, Yang J, Weathersby SP, Park S, Sie EJ, Jarillo-Herrero P, Fisher IR, Wang X, Demler E, Gedik N. Role of Equilibrium Fluctuations in Light-Induced Order. PHYSICAL REVIEW LETTERS 2021; 127:227401. [PMID: 34889631 DOI: 10.1103/physrevlett.127.227401] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
Engineering novel states of matter with light is at the forefront of materials research. An intensely studied direction is to realize broken-symmetry phases that are "hidden" under equilibrium conditions but can be unleashed by an ultrashort laser pulse. Despite a plethora of experimental discoveries, the nature of these orders and how they transiently appear remain unclear. To this end, we investigate a nonequilibrium charge density wave (CDW) in rare-earth tritellurides, which is suppressed in equilibrium but emerges after photoexcitation. Using a pump-pump-probe protocol implemented in ultrafast electron diffraction, we demonstrate that the light-induced CDW consists solely of order parameter fluctuations, which bear striking similarities to critical fluctuations in equilibrium despite differences in the length scale. By calculating the dynamics of CDW fluctuations in a nonperturbative model, we further show that the strength of the light-induced order is governed by the amplitude of equilibrium fluctuations. These findings highlight photoinduced fluctuations as an important ingredient for the emergence of transient orders out of equilibrium. Our results further suggest that materials with strong fluctuations in equilibrium are promising platforms to host hidden orders after laser excitation.
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Affiliation(s)
- Alfred Zong
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA
| | - Pavel E Dolgirev
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Anshul Kogar
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Department of Physics and Astronomy, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Yifan Su
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Joshua A W Straquadine
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
- SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
| | - Xirui Wang
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Duan Luo
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Michael E Kozina
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Alexander H Reid
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Renkai Li
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Jie Yang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | | | - Suji Park
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA
| | - Edbert J Sie
- SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
| | - Pablo Jarillo-Herrero
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Ian R Fisher
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
- SIMES, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Eugene Demler
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Institute for Theoretical Physics, ETH Zurich, 8093 Zurich, Switzerland
| | - Nuh Gedik
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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31
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Monacelli L, Bianco R, Cherubini M, Calandra M, Errea I, Mauri F. The stochastic self-consistent harmonic approximation: calculating vibrational properties of materials with full quantum and anharmonic effects. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:363001. [PMID: 34049302 DOI: 10.1088/1361-648x/ac066b] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/28/2021] [Indexed: 06/12/2023]
Abstract
The efficient and accurate calculation of how ionic quantum and thermal fluctuations impact the free energy of a crystal, its atomic structure, and phonon spectrum is one of the main challenges of solid state physics, especially when strong anharmonicy invalidates any perturbative approach. To tackle this problem, we present the implementation on a modular Python code of the stochastic self-consistent harmonic approximation (SSCHA) method. This technique rigorously describes the full thermodynamics of crystals accounting for nuclear quantum and thermal anharmonic fluctuations. The approach requires the evaluation of the Born-Oppenheimer energy, as well as its derivatives with respect to ionic positions (forces) and cell parameters (stress tensor) in supercells, which can be provided, for instance, by first principles density-functional-theory codes. The method performs crystal geometry relaxation on the quantum free energy landscape, optimizing the free energy with respect to all degrees of freedom of the crystal structure. It can be used to determine the phase diagram of any crystal at finite temperature. It enables the calculation of phase boundaries for both first-order and second-order phase transitions from the Hessian of the free energy. Finally, the code can also compute the anharmonic phonon spectra, including the phonon linewidths, as well as phonon spectral functions. We review the theoretical framework of the SSCHA and its dynamical extension, making particular emphasis on the physical inter pretation of the variables present in the theory that can enlighten the comparison with any other anharmonic theory. A modular and flexible Python environment is used for the implementation, which allows for a clean interaction with other packages. We briefly present a toy-model calculation to illustrate the potential of the code. Several applications of the method in superconducting hydrides, charge-density-wave materials, and thermoelectric compounds are also reviewed.
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Affiliation(s)
- Lorenzo Monacelli
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
| | - Raffaello Bianco
- Centro de Física de Materiales (CSIC-UPV/EHU), Manuel de Lardizabal pasealekua 5, 20018 Donostia/San Sebastián, Spain
| | - Marco Cherubini
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
- Center for Life NanoScience, Istituto Italiano di Tecnologia, Viale ReginaElena 291, 00161 Rome, Italy
| | - Matteo Calandra
- Sorbonne Université, CNRS, Institut des Nanosciences de Paris, UMR7588, F-75252 Paris, France
- Dipartimento di Fisica, Universitá di Trento, Via Sommarive 14, 38123 Povo, Italy
| | - Ion Errea
- Centro de Física de Materiales (CSIC-UPV/EHU), Manuel de Lardizabal pasealekua 5, 20018 Donostia/San Sebastián, Spain
- Fisika Aplikatua Saila, Gipuzkoako Ingeniaritza Eskola, University of the Basque Country (UPV/EHU), Europa Plaza 1, 20018 Donostia/San Sebastián, Spain
- Donostia International Physics Center (DIPC), Manuel Lardizabal pasealekua 4, 20018 Donostia/San Sebastián, Spain
| | - Francesco Mauri
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy
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32
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Wang Q, von Arx K, Horio M, Mukkattukavil DJ, Küspert J, Sassa Y, Schmitt T, Nag A, Pyon S, Takayama T, Takagi H, Garcia-Fernandez M, Zhou KJ, Chang J. Charge order lock-in by electron-phonon coupling in La 1.675Eu 0.2Sr 0.125CuO 4. SCIENCE ADVANCES 2021; 7:eabg7394. [PMID: 34193430 PMCID: PMC8245032 DOI: 10.1126/sciadv.abg7394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 05/17/2021] [Indexed: 06/13/2023]
Abstract
Charge order is universal to all hole-doped cuprates. Yet, the driving interactions remain an unsolved problem. Electron-electron interaction is widely believed to be essential, whereas the role of electron-phonon interaction is unclear. We report an ultrahigh-resolution resonant inelastic x-ray scattering (RIXS) study of the in-plane bond-stretching phonon mode in stripe-ordered cuprate La1.675Eu0.2Sr0.125CuO4 Phonon softening and lifetime shortening are found around the charge ordering wave vector. In addition to these self-energy effects, the electron-phonon coupling is probed by its proportionality to the RIXS cross section. We find an enhancement of the electron-phonon coupling around the charge-stripe ordering wave vector upon cooling into the low-temperature tetragonal structure phase. These results suggest that, in addition to electronic correlations, electron-phonon coupling contributes substantially to the emergence of long-range charge-stripe order in cuprates.
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Affiliation(s)
- Qisi Wang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
| | - Karin von Arx
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
- Department of Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Masafumi Horio
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | | | - Julia Küspert
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Yasmine Sassa
- Department of Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Thorsten Schmitt
- Swiss Light Source, Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - Abhishek Nag
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Sunseng Pyon
- Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
| | - Tomohiro Takayama
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
| | - Hidenori Takagi
- Department of Physics, The University of Tokyo, Tokyo 113-0033, Japan
| | | | - Ke-Jin Zhou
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Johan Chang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
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33
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Lucrezi R, Heil C. Superconductivity and strong anharmonicity in novel Nb-S phases. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:174001. [PMID: 33429377 DOI: 10.1088/1361-648x/abda7a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
In this work we explore the phase diagram of the binary Nb-S system from ambient pressures up to 250 GPa usingab initioevolutionary crystal structure prediction. We find several new stable compositions and phases, especially in the high-pressure regime, and investigate their electronic, vibrational, and superconducting properties. Our calculations show that all materials, besides the low-pressure phases of pure sulfur, are metals with low electron-phonon (ep) coupling strengths and critical superconducting temperatures below 15 K. Furthermore, we investigate the effects of phonon anharmonicity on lattice dynamics, ep interactions, and superconductivity for the novel high-pressure phase of Nb2S, demonstrating that the inclusion of anharmonicity stabilizes the lattice and enhances the ep interaction.
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Affiliation(s)
- Roman Lucrezi
- Institute of Theoretical and Computational Physics, Graz University of Technology, NAWI Graz, 8010 Graz, Austria
| | - Christoph Heil
- Institute of Theoretical and Computational Physics, Graz University of Technology, NAWI Graz, 8010 Graz, Austria
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34
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Roy AP, Bajaj N, Mittal R, Babu PD, Bansal D. Quasi-One-Dimensional Fermi Surface Nesting and Hidden Nesting Enable Multiple Kohn Anomalies in α-Uranium. PHYSICAL REVIEW LETTERS 2021; 126:096401. [PMID: 33750153 DOI: 10.1103/physrevlett.126.096401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 01/20/2021] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
The topology of the Fermi surface controls the electronic response of a metal, including charge density wave (CDW) formation. A topology conducive for Fermi surface nesting (FSN) allows the electronic susceptibility χ_{0} to diverge and induce a CDW at wave vector q_{CDW}. Kohn extended the implications of FSN to show that the imaginary part of the lattice dynamical susceptibility χ_{L}^{''} also responds anomalously for all phonon branches at q_{CDW}-a phenomenon referred to as the Kohn anomaly. However, materials exhibiting multiple Kohn anomalies remain rare. Using first-principles simulations of χ_{0} and χ_{L}^{''}, and previous scattering measurements [Crummett et al., Phys. Rev. B 19, 6028 234 (1979)PRBMDO0163-1829], we show that α-uranium harbors multiple Kohn anomalies enabled by the combined effect of FSN and "hidden" nesting, i.e., nesting of electronic states above and below the Fermi surface. FSN and hidden nesting lead to a ridgelike feature in the real part of χ_{0}, allowing interatomic forces to modulate strongly and multiple Kohn anomalies to emerge. These results emphasize the importance of hidden nesting in controlling χ_{0} and χ_{L}^{''} to exploit electronic and lattice states and enable engineering of advanced materials, including topological Weyl semimetals and superconductors.
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Affiliation(s)
- Aditya Prasad Roy
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
| | - Naini Bajaj
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
| | - Ranjan Mittal
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, MH 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai, MH 400094, India
| | - Peram D Babu
- UGC-DAE Consortium for Scientific Research, Mumbai Centre, R5-Shed, BARC, Trombay, Mumbai, MH 400085, India
| | - Dipanshu Bansal
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
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35
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van der Waals driven anharmonic melting of the 3D charge density wave in VSe 2. Nat Commun 2021; 12:598. [PMID: 33500397 PMCID: PMC7838422 DOI: 10.1038/s41467-020-20829-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 12/22/2020] [Indexed: 11/24/2022] Open
Abstract
Understanding of charge-density wave (CDW) phases is a main challenge in condensed matter due to their presence in high-Tc superconductors or transition metal dichalcogenides (TMDs). Among TMDs, the origin of the CDW in VSe2 remains highly debated. Here, by means of inelastic x-ray scattering and first-principles calculations, we show that the CDW transition is driven by the collapse at 110 K of an acoustic mode at qCDW = (2.25 0 0.7) r.l.u. The softening starts below 225 K and expands over a wide region of the Brillouin zone, identifying the electron-phonon interaction as the driving force of the CDW. This is supported by our calculations that determine a large momentum-dependence of the electron-phonon matrix-elements that peak at the CDW wave vector. Our first-principles anharmonic calculations reproduce the temperature dependence of the soft mode and the TCDW onset only when considering the out-of-plane van der Waals interactions, which reveal crucial for the melting of the CDW phase. The nature of the charge density wave transition in VSe2 is still debated. Here, the authors demonstrate that the transition is mainly driven by electron-phonon interactions, despite the presence of the Fermi-surface nesting, and that Wan-der-Waals forces are responsible for melting of the charge density wave order.
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36
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Kim HH, Lefrançois E, Kummer K, Fumagalli R, Brookes NB, Betto D, Nakata S, Tortora M, Porras J, Loew T, Barber ME, Braicovich L, Mackenzie AP, Hicks CW, Keimer B, Minola M, Le Tacon M. Charge Density Waves in YBa_{2}Cu_{3}O_{6.67} Probed by Resonant X-Ray Scattering under Uniaxial Compression. PHYSICAL REVIEW LETTERS 2021; 126:037002. [PMID: 33543973 DOI: 10.1103/physrevlett.126.037002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/10/2020] [Accepted: 12/14/2020] [Indexed: 06/12/2023]
Abstract
We report a comprehensive Cu L_{3}-edge resonant x-ray scattering (RXS) study of two- and three-dimensional (2D and 3D) incommensurate charge correlations in single crystals of the underdoped high-temperature superconductor YBa_{2}Cu_{3}O_{6.67} under uniaxial compression up to 1% along the two inequivalent Cu─O─Cu bond directions (a and b) in the CuO_{2} planes. We confirm the strong in-plane anisotropy of the 2D charge correlations and observe their symmetric response to pressure: pressure along a enhances correlations along b, and vice versa. Our results imply that the underlying order parameter is uniaxial. In contrast, 3D long-range charge order is only observed along b in response to compression along a. Spectroscopic RXS measurements show that the 3D charge order resides exclusively in the CuO_{2} planes and may thus be generic to the cuprates. We discuss implications of these results for models of electronic nematicity and for the interplay between charge order and superconductivity.
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Affiliation(s)
- H-H Kim
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - E Lefrançois
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - K Kummer
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
| | - R Fumagalli
- Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - N B Brookes
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
| | - D Betto
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
| | - S Nakata
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Tortora
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - J Porras
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - T Loew
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M E Barber
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany
| | - L Braicovich
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, F-38043 Grenoble, France
- Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - A P Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, United Kingdom
| | - C W Hicks
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany
| | - B Keimer
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Minola
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - M Le Tacon
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
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37
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Hossain M, Iqbal MA, Wu J, Xie L. Chemical vapor deposition and temperature-dependent Raman characterization of two-dimensional vanadium ditelluride. RSC Adv 2021; 11:2624-2629. [PMID: 35424251 PMCID: PMC8693834 DOI: 10.1039/d0ra07868a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 12/22/2020] [Indexed: 11/21/2022] Open
Abstract
Recently, ultrathin two-dimensional (2D) metallic vanadium dichalcogenides have attracted widespread attention because of the charge density wave (CDW) phase transition and possible ferromagnetism. Herein, we report the synthesis and temperature-dependent Raman characterization of the 2D vanadium ditelluride (VTe2). The synthesis is done by atmospheric pressure chemical vapor deposition (APCVD) using vanadium chloride (VCl3) precursor on fluorphlogopite mica, sapphire, and h-BN substrates. A large area of the thin film with thickness ∼10 nm is grown on the hexagonal boron nitride (h-BN) substrate. Temperature-dependent Raman characterization of VTe2 is conducted from room temperature to 513 K. Remarkable changes of Raman modes at around 413 K are observed, indicating the structural phase transition. Two-dimensional vanadium ditelluride has been synthesized on mica, sapphire, and h-BN substrates by atmospheric pressure chemical vapor deposition.![]()
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Affiliation(s)
- Mongur Hossain
- Hunan Key Laboratory of Two-Dimensional Materials, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University Changsha 410082 P. R. China .,CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology Beijing 100190 P. R. China .,University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Muhammad Ahsan Iqbal
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology Beijing 100190 P. R. China .,University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Juanxia Wu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology Beijing 100190 P. R. China
| | - Liming Xie
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology Beijing 100190 P. R. China .,University of Chinese Academy of Sciences Beijing 100049 P. R. China
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38
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Chowdhury S, Hill HM, Rigosi AF, Briggs A, Berger H, Newell DB, Walker ARH, Tavazza F. Examining Experimental Raman Mode Behavior in Mono- and Bilayer 2H-TaSe 2 via Density Functional Theory: Implications for Quantum Information Science. ACS APPLIED NANO MATERIALS 2021; 4:10.1021/acsanm.0c03222. [PMID: 34250452 PMCID: PMC8268966 DOI: 10.1021/acsanm.0c03222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Tantalum diselenide (TaSe2) is a metallic transition metal dichalcogenide whose structure and vibrational behavior strongly depend on temperature and thickness, and this behavior includes the emergence of charge density wave (CDW) states at very low temperatures. In this work, observed Raman modes for mono- and bilayer are described across several spectral regions and compared to those seen in the bulk case. These modes, which include an experimentally observed forbidden Raman mode and low-frequency CDWs, are then matched to corresponding vibrations predicted by density functional theory (DFT). The reported match between experimental and computational results supports the presented vibrational visualizations of these modes. Support is also provided by experimental phonons observed in additional Raman spectra as a function of temperature and thickness. These results highlight the importance of understanding CDWs since they are likely to play a fundamental role in the future realization of solid-state quantum information platforms based on nonequilibrium phenomena.
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Affiliation(s)
- Sugata Chowdhury
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States; Department of Physics and Astronomy, Howard University, Washington, D.C. 20059, United States
| | - Heather M Hill
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Albert F Rigosi
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Andrew Briggs
- National Institute of Standards and, Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Helmuth Berger
- École Polytechnique Fédérale de Lausanne (EPFL), Institut de Physique des Nanostructures, CH-1015 Lausanne, Switzerland
| | - David B Newell
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Angela R Hight Walker
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Francesca Tavazza
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
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39
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Measuring the Electron–Phonon Interaction in Two-Dimensional Superconductors with He-Atom Scattering. CONDENSED MATTER 2020. [DOI: 10.3390/condmat5040079] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Helium-atom scattering (HAS) spectroscopy from conducting surfaces has been shown to provide direct information on the electron–phonon interaction, more specifically the mass-enhancement factor λ from the temperature dependence of the Debye–Waller exponent, and the mode-selected electron–phonon coupling constants λQν from the inelastic HAS intensities from individual surface phonons. The recent applications of the method to superconducting ultra-thin films, quasi-1D high-index surfaces, and layered transition-metal and topological pnictogen chalcogenides are briefly reviewed.
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40
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Chen Y, Wu L, Xu H, Cong C, Li S, Feng S, Zhang H, Zou C, Shang J, Yang SA, Loh KP, Huang W, Yu T. Visualizing the Anomalous Charge Density Wave States in Graphene/NbSe 2 Heterostructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2003746. [PMID: 33002238 DOI: 10.1002/adma.202003746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/29/2020] [Indexed: 06/11/2023]
Abstract
Metallic layered transition metal dichalcogenides (TMDs) host collective many-body interactions, including the competing superconducting and charge density wave (CDW) states. Graphene is widely employed as a heteroepitaxial substrate for the growth of TMD layers and as an ohmic contact, where the graphene/TMD heterostructure is naturally formed. The presence of graphene can unpredictably influence the CDW order in 2D CDW conductors. This work reports the CDW transitions of 2H-NbSe2 layers in graphene/NbSe2 heterostructures. The evolution of Raman spectra demonstrates that the CDW phase transition temperatures (TCDW ) of NbSe2 are dramatically decreased when capped by graphene. The induced anomalous short-range CDW state is confirmed by scanning tunneling microscopy measurements. The findings propose a new criterion to determine the TCDW through monitoring the line shape of the A1g mode. Meanwhile, the 2D band is also discovered as an indicator to observe the CDW transitions. First-principles calculations imply that interfacial electron doping suppresses the CDW states by impeding the lattice distortion of 2H-NbSe2 . The extraordinary random CDW lattice suggests deep insight into the formation mechanism of many collective electronic states and possesses great potential in modulating multifunctional devices.
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Affiliation(s)
- Yu Chen
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), Xi'an, 710129, China
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Lishu Wu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Hai Xu
- Department of Chemistry, National University of Singapore, Singapore, 117543, Singapore
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Science, Changchun, 130033, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100040, China
| | - Chunxiao Cong
- State Key Laboratory of ASIC and System, School of Information Science and Technology, Fudan University, Shanghai, 200433, China
- Academy for Engineering and Technology, Fudan University, Shanghai, 200433, China
| | - Si Li
- Research Laboratory for Quantum Materials, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Shun Feng
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Hongbo Zhang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Chenji Zou
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Jingzhi Shang
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), Xi'an, 710129, China
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Shengyuan A Yang
- Research Laboratory for Quantum Materials, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Kian Ping Loh
- Department of Chemistry, National University of Singapore, Singapore, 117543, Singapore
| | - Wei Huang
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), Xi'an, 710129, China
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing, 211800, China
| | - Ting Yu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
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41
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Kvashnin Y, VanGennep D, Mito M, Medvedev SA, Thiyagarajan R, Karis O, Vasiliev AN, Eriksson O, Abdel-Hafiez M. Coexistence of Superconductivity and Charge Density Waves in Tantalum Disulfide: Experiment and Theory. PHYSICAL REVIEW LETTERS 2020; 125:186401. [PMID: 33196259 DOI: 10.1103/physrevlett.125.186401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/18/2020] [Accepted: 09/25/2020] [Indexed: 06/11/2023]
Abstract
The coexistence of charge density wave (CDW) and superconductivity in tantalum disulfide (2H-TaS_{2}) at low temperature is boosted by applying hydrostatic pressures to study both vibrational and magnetic transport properties. Around P_{c}, we observe a superconducting dome with a maximum superconducting transition temperature T_{c}=9.1 K. First-principles calculations of the electronic structure predict that, under ambient conditions, the undistorted structure is characterized by a phonon instability at finite momentum close to the experimental CDW wave vector. Upon compression, this instability is found to disappear, indicating the suppression of CDW order. The calculations reveal an electronic topological transition (ETT), which occurs before the suppression of the phonon instability, suggesting that the ETT alone is not directly causing the structural change in the system. The temperature dependence of the first vortex penetration field has been experimentally obtained by two independent methods. While a d wave and single-gap BCS prediction cannot describe the lower critical field H_{c1} data, the temperature dependence of the H_{c1} can be well described by a single-gap anisotropic s-wave order parameter.
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Affiliation(s)
- Y Kvashnin
- Uppsala University, Department of Physics and Astronomy, Box 516, SE-751 20 Uppsala, Sweden
| | - D VanGennep
- Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - M Mito
- Graduate School of Engineering, Kyushu Institute of Technology, Fukuoka 804-8550, Japan
| | - S A Medvedev
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - R Thiyagarajan
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01069 Dresden, Germany
| | - O Karis
- Uppsala University, Department of Physics and Astronomy, Box 516, SE-751 20 Uppsala, Sweden
| | - A N Vasiliev
- Ural Federal University, Yekaterinburg 620002, Russia
- Lomonosov Moscow State University, Moscow 119991, Russia
- National Research South Ural State University, Chelyabinsk 454080, Russia
| | - O Eriksson
- Uppsala University, Department of Physics and Astronomy, Box 516, SE-751 20 Uppsala, Sweden
- School of Science and Technology, Örebro University, SE-701 82 Örebro, Sweden
| | - M Abdel-Hafiez
- Uppsala University, Department of Physics and Astronomy, Box 516, SE-751 20 Uppsala, Sweden
- Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
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42
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Bianco R, Monacelli L, Calandra M, Mauri F, Errea I. Weak Dimensionality Dependence and Dominant Role of Ionic Fluctuations in the Charge-Density-Wave Transition of NbSe_{2}. PHYSICAL REVIEW LETTERS 2020; 125:106101. [PMID: 32955304 DOI: 10.1103/physrevlett.125.106101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Contradictory experiments have been reported about the dimensionality effect on the charge-density-wave transition in 2H NbSe_{2}. While scanning tunneling experiments on single layers grown by molecular beam epitaxy measure a charge-density-wave transition temperature in the monolayer similar to the bulk, around 33 K, Raman experiments on exfoliated samples observe a large enhancement of the transition temperature up to 145 K. By employing a nonperturbative approach to deal with anharmonicity, we calculate from first principles the temperature dependence of the phonon spectra both for bulk and monolayer. In both cases, the charge-density-wave transition temperature is estimated as the temperature at which the phonon energy of the mode driving the structural instability vanishes. The obtained transition temperature in the bulk is around 59 K, in rather good agreement with experiments, and it is just slightly increased in the single-layer limit to 73 K, showing the weak dependence of the transition on dimensionality. Environmental factors could motivate the disagreement between the transition temperatures reported by experiments. Our analysis also demonstrates the predominance of ionic fluctuations over electronic ones in the melting of the charge-density-wave order.
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Affiliation(s)
- Raffaello Bianco
- Centro de Física de Materiales (CSIC-UPV/EHU), Manuel de Lardizabal pasealekua 5, 20018 Donostia/San Sebastián, Spain
| | - Lorenzo Monacelli
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, I-00185 Roma, Italy
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, I-16163 Genova, Italy
| | - Matteo Calandra
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, I-16163 Genova, Italy
- Dipartimento di Fisica, Università di Trento, Via Sommarive 14, 38123 Povo, Italy
- Sorbonne Université, CNRS, Institut des Nanosciences de Paris, UMR7588, F-75252 Paris, France
| | - Francesco Mauri
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, I-00185 Roma, Italy
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, I-16163 Genova, Italy
| | - Ion Errea
- Centro de Física de Materiales (CSIC-UPV/EHU), Manuel de Lardizabal pasealekua 5, 20018 Donostia/San Sebastián, Spain
- Fisika Aplikatua 1 Saila, Gipuzkoako Ingeniaritza Eskola, University of the Basque Country (UPV/EHU), Europa Plaza 1, 20018 Donostia/San Sebastián, Spain
- Donostia International Physics Center (DIPC), Manuel Lardizabal pasealekua 4, 20018 Donostia/San Sebastián, Spain
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43
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Peng YY, Husain AA, Mitrano M, Sun SXL, Johnson TA, Zakrzewski AV, MacDougall GJ, Barbour A, Jarrige I, Bisogni V, Abbamonte P. Enhanced Electron-Phonon Coupling for Charge-Density-Wave Formation in La_{1.8-x}Eu_{0.2}Sr_{x}CuO_{4+δ}. PHYSICAL REVIEW LETTERS 2020; 125:097002. [PMID: 32915627 DOI: 10.1103/physrevlett.125.097002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 03/04/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Charge density wave (CDW) correlations are prevalent in all copper-oxide superconductors. While CDWs in conventional metals are driven by coupling between lattice vibrations and electrons, the role of the electron-phonon coupling (EPC) in cuprate CDWs is strongly debated. Using Cu L_{3} edge resonant inelastic x-ray scattering, we study the CDW and Cu-O bond-stretching phonons in the stripe-ordered cuprate La_{1.8-x}Eu_{0.2}Sr_{x}CuO_{4+δ}. We investigate the interplay between charge order and EPC as a function of doping and temperature and find that the EPC is enhanced in a narrow momentum region around the CDW ordering vector. By detuning the incident photon energy from the absorption resonance, we extract an EPC matrix element at the CDW ordering vector of M≃0.36 eV, which decreases to M≃0.30 eV at high temperature in the absence of the CDW. Our results suggest a feedback mechanism in which the CDW enhances the EPC which, in turn, further stabilizes the CDW.
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Affiliation(s)
- Y Y Peng
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - A A Husain
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - M Mitrano
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - S X-L Sun
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - T A Johnson
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - A V Zakrzewski
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - G J MacDougall
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
| | - A Barbour
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - I Jarrige
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - V Bisogni
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - P Abbamonte
- Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
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44
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Mano P, Minamitani E, Watanabe S. Straintronic effect for superconductivity enhancement in Li-intercalated bilayer MoS 2. NANOSCALE ADVANCES 2020; 2:3150-3155. [PMID: 36134288 PMCID: PMC9416899 DOI: 10.1039/d0na00420k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/03/2020] [Indexed: 06/13/2023]
Abstract
In this study, ab initio calculations were performed to show that the superconductivity in Li-intercalated bilayer MoS2 could be enhanced by applying either compressive or tensile strain. Moreover, the mechanism for superconductivity enhancement for the tensile strain case was found to be different than that of the compressive strain case. Enhanced electron phonon coupling (EPC) under tensile strain could be explained by an increase in the nesting function involved with the change in the Fermi surface topology in a wide range of Brillouin zones. The superconducting transition temperature T c of 0.46 K at zero strain increased up to 9.12 K under a 6.0% tensile strain. Meanwhile, the enhancement in compressive strain was attributed to the increase in intrinsic electron phonon matrix elements. Furthermore, the contribution from interband scattering was large, which suggested the importance of electron pockets on the Fermi surface. Finally, 80% of the total EPC (λ = 0.98) originated from these pockets and the estimated T c was 13.50 K.
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Affiliation(s)
- Poobodin Mano
- Department of Materials Engineering, The University of Tokyo 7-3-1 Hongo Bunkyo Tokyo 113-8656 Japan
| | - Emi Minamitani
- Institute for Molecular Science 38 Nishigo-Naka, Myodaiji Okazaki Aichi 444-8585 Japan
| | - Satoshi Watanabe
- Department of Materials Engineering, The University of Tokyo 7-3-1 Hongo Bunkyo Tokyo 113-8656 Japan
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45
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Rubio-Verdú C, Garcı A-Garcı A AM, Ryu H, Choi DJ, Zaldı Var J, Tang S, Fan B, Shen ZX, Mo SK, Pascual JI, Ugeda MM. Visualization of Multifractal Superconductivity in a Two-Dimensional Transition Metal Dichalcogenide in the Weak-Disorder Regime. NANO LETTERS 2020; 20:5111-5118. [PMID: 32463696 DOI: 10.1021/acs.nanolett.0c01288] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Eigenstate multifractality is a distinctive feature of noninteracting disordered metals close to a metal-insulator transition, whose properties are expected to extend to superconductivity. While multifractality in three dimensions (3D) only develops near the critical point for specific strong-disorder strengths, multifractality in 2D systems is expected to be observable even for weak disorder. Here we provide evidence for multifractal features in the superconducting state of an intrinsic, weakly disordered single-layer NbSe2 by means of low-temperature scanning tunneling microscopy/spectroscopy. The superconducting gap, characterized by its width, depth, and coherence peaks' amplitude, shows a characteristic spatial modulation coincident with the periodicity of the quasiparticle interference pattern. The strong spatial inhomogeneity of the superconducting gap width, proportional to the local order parameter in the weak-disorder regime, follows a log-normal statistical distribution as well as a power-law decay of the two-point correlation function, in agreement with our theoretical model. Furthermore, the experimental singularity spectrum f(α) shows anomalous scaling behavior typical from 2D weakly disordered systems.
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Affiliation(s)
| | - Antonio M Garcı A-Garcı A
- Shanghai Center for Complex Physics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hyejin Ryu
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Center for Spintronics, Korean Institute of Science and Technology, Seoul 02792, Korea
| | - Deung-Jang Choi
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU), 20018 San Sebastián, Spain
- Donostia International Physics Center (DIPC), 20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | | | - Shujie Tang
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Bo Fan
- Shanghai Center for Complex Physics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhi-Xun Shen
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Geballe Laboratory for Advanced Materials, Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, United States
| | - Sung-Kwan Mo
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - José Ignacio Pascual
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Miguel M Ugeda
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU), 20018 San Sebastián, Spain
- Donostia International Physics Center (DIPC), 20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
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46
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Frano A, Blanco-Canosa S, Keimer B, Birgeneau RJ. Charge ordering in superconducting copper oxides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:374005. [PMID: 31829986 DOI: 10.1088/1361-648x/ab6140] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Charge order has recently been identified as a leading competitor of high-temperature superconductivity in moderately doped cuprates. We provide a survey of universal and materials-specific aspects of this phenomenon, with emphasis on results obtained by scattering methods. In particular, we discuss the structure, periodicity, and stability range of the charge-ordered state, its response to various external perturbations, the influence of disorder, the coexistence and competition with superconductivity, as well as collective charge dynamics. In the context of this journal issue which honors Roger Cowley's legacy, we also discuss the connection of charge ordering with lattice vibrations and the central-peak phenomenon. We end the review with an outlook on research opportunities offered by new synthesis methods and experimental platforms, including cuprate thin films and superlattices.
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Affiliation(s)
- Alex Frano
- Department of Physics, University of California, San Diego, CA 92093, United States of America
| | - Santiago Blanco-Canosa
- Donostia International Physics Center, DIPC, 20018 Donostia-San Sebastian, Basque Country, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Basque Country, Spain
| | - Bernhard Keimer
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - Robert J Birgeneau
- Department of Physics, University of California, Berkeley, CA 94720, United States of America
- Department of Materials Science and Engineering, University of California Berkeley, Berkeley, CA 94720, United States of America
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47
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Zhai X, Xu X, Peng J, Jing F, Zhang Q, Liu H, Hu Z. Enhanced Optoelectronic Performance of CVD-Grown Metal-Semiconductor NiTe 2/MoS 2 Heterostructures. ACS APPLIED MATERIALS & INTERFACES 2020; 12:24093-24101. [PMID: 32374152 DOI: 10.1021/acsami.0c02166] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Van der Waals (vdW) heterostructures are the fundamental blocks for two-dimensional (2D) electronic and optoelectronic devices. In this work, a high-quality 2D metal-semiconductor NiTe2/MoS2 heterostructure is prepared by a two-step chemical vapor deposition (CVD) growth. The back-gated field-effect transistors (FETs) and photodetectors based on the heterostructure show enhanced electronic and optoelectronic performance than that of a pristine MoS2 monolayer, owing to the better heterointerface in the former device. Especially, this photodetector based on the metal-semiconductor heterostructure shows 3 orders faster rise time and decay time than that of the pristine MoS2 under the same fabrication procedure. The enhancement of electronic behavior and optoelectronic response by the epitaxial growth of metallic vdW layered materials can provide a new method to improve the performance of optoelectronic devices.
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Affiliation(s)
- Xiaokun Zhai
- School of Physics and Electronics, Hunan University, Changsha, Hunan 410082, China
- Institute of Functional Crystals, Tianjin University of Technology, Tianjin 300384, China
| | - Xing Xu
- School of Physics and Electronics, Hunan University, Changsha, Hunan 410082, China
| | - Jiangbo Peng
- School of Physics and Electronics, Hunan University, Changsha, Hunan 410082, China
- Institute of Functional Crystals, Tianjin University of Technology, Tianjin 300384, China
| | - Fangli Jing
- Tianjin Key Laboratory of Functional Crystal Materials, Tianjin University of Technology, Tianjin 300384, China
- Department of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Qinglin Zhang
- School of Physics and Electronics, Hunan University, Changsha, Hunan 410082, China
| | - Hongjun Liu
- School of Physics and Electronics, Hunan University, Changsha, Hunan 410082, China
- Institute of Functional Crystals, Tianjin University of Technology, Tianjin 300384, China
- Tianjin Key Laboratory of Functional Crystal Materials, Tianjin University of Technology, Tianjin 300384, China
| | - Zhanggui Hu
- Institute of Functional Crystals, Tianjin University of Technology, Tianjin 300384, China
- Tianjin Key Laboratory of Functional Crystal Materials, Tianjin University of Technology, Tianjin 300384, China
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48
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Xue Y, Zhang Y, Wang H, Lin S, Li Y, Dai JY, Lau SP. Thickness-dependent magnetotransport properties in 1T VSe 2 single crystals prepared by chemical vapor deposition. NANOTECHNOLOGY 2020; 31:145712. [PMID: 31860893 DOI: 10.1088/1361-6528/ab6478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Two-dimensional (2D) metallic transition metal dichalcogenides (TMDs) exhibit fascinating quantum effects, such as charge-density-wave (CDW) and weak antilocalization (WAL) effect. Herein, low temperature synthesis of 1T phase VSe2 single crystals with thickness ranging from 3 to 41 nm by chemical vapor deposition (CVD) is reported. The VSe2 shows a decreasing phase transition temperature of the CDW when the thickness is decreased. Moreover, low-temperature magnetotransport measurements demonstrate a linear positive and non-saturating magnetoresistance (MR) of 35% from a 35 nm thick VSe2 at 15 T and 2 K due to CDW induce mobility fluctuations. Surprisingly, Kohler's rule analysis of the MR reveals the non-applicability of Kohler's rule for temperature above 50 K indicating that the MR behavior cannot be described in terms of semiclassical transport on a single Fermi surface with a single scattering time. Furthermore, WAL effect is observed in the 4.2 nm thick VSe2 at low magnetic fields at 2 K, revealing the contribution of the quantum interference effect at the 2D limit. The phase coherence length [Formula: see text] and spin-orbit scattering length [Formula: see text] were determined to be 73 nm and 18 nm at 2 K, respectively. Our work opens new avenues to study the fundamental quantum phenomena in CVD-deposited TMDs.
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Affiliation(s)
- Yunzhou Xue
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, People's Republic of China
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49
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Manikandan K, Pervin R, Saravanan C, Sathiskumar M, Chakraborty N, Shirage PM, Mondal S, Srihari V, Poswal HK, Arumugam S. Influence of pressure on the transport, magnetic, and structural properties of superconducting Cr 0.0009NbSe 2 single crystal. RSC Adv 2020; 10:13112-13125. [PMID: 35492110 PMCID: PMC9051428 DOI: 10.1039/c9ra09603e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/07/2020] [Indexed: 11/21/2022] Open
Abstract
We investigate the superconducting critical current density (J c), transition temperature (T c), and flux pinning properties under hydrostatic pressure (P) for Cr0.0009NbSe2 single crystal. The application of P enhances T c in both electrical resistivity (∼0.38 K GPa-1: 0 ≤ P ≤ 2.5 GPa) and magnetization (∼0.98 K GPa-1: 0 ≤ P ≤ 1 GPa) measurements, which leads to a monotonic increase in J c and flux pinning properties. The field-dependent J c at various temperatures under P is analyzed within the collecting pinning theory and it shows that δT c pinning is the crossover to δl pinning above the critical pressure (P c ∼0.3 GPa). Our systematic analysis of the flux pinning mechanism indicates that both the density of pinning centers and pinning forces greatly increase with the application of P, which leads to an enhancement in the vortex state. Structural studies using synchrotron X-ray diffraction under pressure illustrate a stable hexagonal phase without any significant impurity phase and lattice parameter reduction with P shows highly anisotropic nature.
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Affiliation(s)
- K Manikandan
- Centre for High Pressure Research, School of Physics, Bharathidasan University Tiruchirappalli-620024 India +91 431 2407045 +91 431 2407118 +91 9500910310
| | - Rukshana Pervin
- Discipline of Metallurgy Engineering and Materials Science & Physics, Indian Institute of Technology Indore Simrol Campus, Khandwa Road Indore 453552 India
| | - C Saravanan
- Centre for High Pressure Research, School of Physics, Bharathidasan University Tiruchirappalli-620024 India +91 431 2407045 +91 431 2407118 +91 9500910310
| | - M Sathiskumar
- Centre for High Pressure Research, School of Physics, Bharathidasan University Tiruchirappalli-620024 India +91 431 2407045 +91 431 2407118 +91 9500910310
| | - Nirman Chakraborty
- CSIR-Central Glass and Ceramic Research Institute Jadavpur Kolkata 700 032 India
| | - Parasharam M Shirage
- Discipline of Metallurgy Engineering and Materials Science & Physics, Indian Institute of Technology Indore Simrol Campus, Khandwa Road Indore 453552 India
| | - Swastik Mondal
- CSIR-Central Glass and Ceramic Research Institute Jadavpur Kolkata 700 032 India
| | - Velaga Srihari
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre Mumbai 400085 India
| | - Himanshu Kumar Poswal
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre Mumbai 400085 India
| | - S Arumugam
- Centre for High Pressure Research, School of Physics, Bharathidasan University Tiruchirappalli-620024 India +91 431 2407045 +91 431 2407118 +91 9500910310
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50
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Hou XY, Zhang F, Tu XH, Gu YD, Zhang MD, Gong J, Tu YB, Wang BT, Lv WG, Weng HM, Ren ZA, Chen GF, Zhu XD, Hao N, Shan L. Inelastic Electron Tunneling in 2H-Ta_{x}Nb_{1-x}Se_{2} Evidenced by Scanning Tunneling Spectroscopy. PHYSICAL REVIEW LETTERS 2020; 124:106403. [PMID: 32216384 DOI: 10.1103/physrevlett.124.106403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/29/2020] [Accepted: 02/11/2020] [Indexed: 06/10/2023]
Abstract
We report a detailed study of tunneling spectra measured on 2H-Ta_{x}Nb_{1-x}Se_{2} (x=0∼0.1) single crystals using a low-temperature scanning tunneling microscope. The prominent gaplike feature, which has not been understood for a long time, was found to be accompanied by some "in-gap" fine structures. By investigating the second-derivative spectra and their temperature and magnetic field dependencies, we were able to prove that inelastic electron tunneling is the origin of these features and obtain the Eliashberg function of 2H-Ta_{x}Nb_{1-x}Se_{2} at an atomic scale, providing a potential way to study the local Eliashberg function and the phonon spectra of the related transition-metal dichalcogenides.
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Affiliation(s)
- Xing-Yuan Hou
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Fan Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Xin-Hai Tu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Ya-Dong Gu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Meng-Di Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Jing Gong
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Yu-Bing Tu
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Bao-Tian Wang
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Wen-Gang Lv
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hong-Ming Weng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zhi-An Ren
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Gen-Fu Chen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Xiang-De Zhu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Ning Hao
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Lei Shan
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
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