1
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Jiang YX, Shao S, Xia W, Denner MM, Ingham J, Hossain MS, Qiu Q, Zheng X, Chen H, Cheng ZJ, Yang XP, Kim B, Yin JX, Zhang S, Litskevich M, Zhang Q, Cochran TA, Peng Y, Chang G, Guo Y, Thomale R, Neupert T, Hasan MZ. Van Hove annihilation and nematic instability on a kagome lattice. NATURE MATERIALS 2024:10.1038/s41563-024-01914-z. [PMID: 39009656 DOI: 10.1038/s41563-024-01914-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 05/06/2024] [Indexed: 07/17/2024]
Abstract
A nematic phase breaks the point-group symmetry of the crystal lattice and is known to emerge in correlated materials. Here we report the observation of an intra-unit-cell nematic order and associated Fermi surface deformation in the kagome metal ScV6Sn6. Using scanning tunnelling microscopy and scanning tunnelling spectroscopy, we reveal a stripe-like nematic order breaking the crystal rotational symmetry within the kagome lattice itself. Moreover, we identify a set of Van Hove singularities adhering to the kagome-layer electrons, which appear along one direction of the Brillouin zone and are annihilated along other high-symmetry directions, revealing rotational symmetry breaking. Via detailed spectroscopic maps, we further observe an elliptical deformation of the Fermi surface, which provides direct evidence for an electronically mediated nematic order. Our work not only bridges the gap between electronic nematicity and kagome physics but also sheds light on the potential mechanism for realizing symmetry-broken phases in correlated electron systems.
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Affiliation(s)
- Yu-Xiao Jiang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA.
| | - Sen Shao
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Wei Xia
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, China
- ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai, China
| | - M Michael Denner
- Department of Physics, University of Zürich, Zürich, Switzerland
| | - Julian Ingham
- Department of Physics, Columbia University, New York, NY, USA
| | - Md Shafayat Hossain
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Qingzheng Qiu
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Xiquan Zheng
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Hongyu Chen
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Zi-Jia Cheng
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Xian P Yang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Byunghoon Kim
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Jia-Xin Yin
- Department of physics, Southern University of Science and Technology, Shenzhen, China
| | - Songbo Zhang
- Department of Physics, University of Zürich, Zürich, Switzerland
| | - Maksim Litskevich
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Qi Zhang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Tyler A Cochran
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA
| | - Yingying Peng
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Guoqing Chang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Yanfeng Guo
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, China
- ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai, China
| | - Ronny Thomale
- Institut für Theoretische Physik und Astrophysik, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Titus Neupert
- Department of Physics, University of Zürich, Zürich, Switzerland
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, USA.
- Quantum Science Center, Oak Ridge, TN, USA.
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2
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Bluschke M, Gupta NK, Jang H, Husain AA, Lee B, Kim M, Na M, Dos Remedios B, Smit S, Moen P, Park SY, Kim M, Jang D, Choi H, Sutarto R, Reid AH, Dakovski GL, Coslovich G, Nguyen QL, Burdet NG, Lin MF, Revcolevschi A, Park JH, Geck J, Turner JJ, Damascelli A, Hawthorn DG. Orbital-selective time-domain signature of nematicity dynamics in the charge-density-wave phase of La 1.65Eu 0.2Sr 0.15CuO 4. Proc Natl Acad Sci U S A 2024; 121:e2400727121. [PMID: 38819998 PMCID: PMC11161785 DOI: 10.1073/pnas.2400727121] [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: 01/12/2024] [Accepted: 04/25/2024] [Indexed: 06/02/2024] Open
Abstract
Understanding the interplay between charge, nematic, and structural ordering tendencies in cuprate superconductors is critical to unraveling their complex phase diagram. Using pump-probe time-resolved resonant X-ray scattering on the (0 0 1) Bragg peak at the Cu [Formula: see text] and O [Formula: see text] resonances, we investigate nonequilibrium dynamics of [Formula: see text] nematic order and its association with both charge density wave (CDW) order and lattice dynamics in La[Formula: see text]Eu[Formula: see text]Sr[Formula: see text]CuO[Formula: see text]. The orbital selectivity of the resonant X-ray scattering cross-section allows nematicity dynamics associated with the planar O 2[Formula: see text] and Cu 3[Formula: see text] states to be distinguished from the response of anisotropic lattice distortions. A direct time-domain comparison of CDW translational-symmetry breaking and nematic rotational-symmetry breaking reveals that these broken symmetries remain closely linked in the photoexcited state, consistent with the stability of CDW topological defects in the investigated pump fluence regime.
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Affiliation(s)
- Martin Bluschke
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - Naman K. Gupta
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ONN2L 3G1, Canada
| | - Hoyoung Jang
- X-ray Free Electron Laser Beamline Division, Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang37673, Gyeongbuk, Republic of Korea
- Photon Science Center, Pohang University of Science and Technology, Pohang37673, Gyeongbuk, Republic of Korea
| | - Ali. A. Husain
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - Byungjune Lee
- Max Planck - Pohang University of Science and Technology/Korea Research Initiative, Center for Complex Phase Materials, Pohang37673, Republic of Korea
- Department of Physics, Pohang University of Science and Technology, Pohang37673, Republic of Korea
| | - Minjune Kim
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - MengXing Na
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - Brandon Dos Remedios
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - Steef Smit
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - Peter Moen
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - Sang-Youn Park
- X-ray Free Electron Laser Beamline Division, Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang37673, Gyeongbuk, Republic of Korea
| | - Minseok Kim
- X-ray Free Electron Laser Beamline Division, Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang37673, Gyeongbuk, Republic of Korea
| | - Dogeun Jang
- X-ray Free Electron Laser Beamline Division, Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang37673, Gyeongbuk, Republic of Korea
| | - Hyeongi Choi
- X-ray Free Electron Laser Beamline Division, Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang37673, Gyeongbuk, Republic of Korea
| | | | - Alexander H. Reid
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
| | - Georgi L. Dakovski
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
| | - Giacomo Coslovich
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
| | - Quynh L. Nguyen
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
- Stanford PULSE Institute, Stanford University and Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
| | - Nicolas G. Burdet
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
- Stanford Institute for Materials and Energy Sciences, Stanford Linear Accelerator Center National Accelerator Laboratory and Stanford University, Menlo Park, CA94025
| | - Ming-Fu Lin
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
| | - Alexandre Revcolevschi
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, Université Paris-Saclay, Centre National de la Recherche Scientifique, UMR 8182, 91405Orsay, France
| | - Jae-Hoon Park
- Max Planck - Pohang University of Science and Technology/Korea Research Initiative, Center for Complex Phase Materials, Pohang37673, Republic of Korea
- Department of Physics, Pohang University of Science and Technology, Pohang37673, Republic of Korea
| | - Jochen Geck
- Institute of Solid State and Materials Physics, Technische Universität Dresden, 01069Dresden, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062Dresden, Germany
| | - Joshua J. Turner
- Linac Coherent Light Source, Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, CA94025
- Stanford Institute for Materials and Energy Sciences, Stanford Linear Accelerator Center National Accelerator Laboratory and Stanford University, Menlo Park, CA94025
| | - Andrea Damascelli
- Quantum Matter Institute, University of British Columbia, Vancouver, BCV6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BCV6T 1Z1, Canada
| | - David G. Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ONN2L 3G1, Canada
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3
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Zhang X, Carbin T, Culver AB, Du K, Wang K, Cheong SW, Roy R, Kogar A. Light-induced electronic polarization in antiferromagnetic Cr 2O 3. NATURE MATERIALS 2024; 23:790-795. [PMID: 38561519 DOI: 10.1038/s41563-024-01852-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 03/06/2024] [Indexed: 04/04/2024]
Abstract
In a solid, the electronic subsystem can exhibit incipient order with lower point group symmetry than the crystal lattice. Ultrafast external fields that couple exclusively to electronic order parameters have rarely been investigated, however, despite their potential importance in inducing exotic effects. Here we show that when inversion symmetry is broken by the antiferromagnetic order in Cr2O3, transmitting a linearly polarized light pulse through the crystal gives rise to an in-plane rotational symmetry-breaking (from C3 to C1) via optical rectification. Using interferometric time-resolved second harmonic generation, we show that the ultrafast timescale of the symmetry reduction is indicative of a purely electronic response; the underlying spin and crystal structures remain unaffected. The symmetry-broken state exhibits a dipole moment, and its polar axis can be controlled with the incident light. Our results establish a coherent nonlinear optical protocol by which to break electronic symmetries and produce unconventional electronic effects in solids.
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Affiliation(s)
- Xinshu Zhang
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA
| | - Tyler Carbin
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA
| | - Adrian B Culver
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA
- Mani L. Bhaumik Institute for Theoretical Physics, Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA
| | - Kai Du
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ, USA
| | - Kefeng Wang
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ, USA
| | - Sang-Wook Cheong
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ, USA
| | - Rahul Roy
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA
- Mani L. Bhaumik Institute for Theoretical Physics, Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA
| | - Anshul Kogar
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA.
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4
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Yang H, Luo Y, Jin B, Chi S, Li X. Convoluted micellar morphological transitions driven by tailorable mesogenic ordering effect from discotic mesogen-containing block copolymer. Nat Commun 2024; 15:2968. [PMID: 38580629 PMCID: PMC10997646 DOI: 10.1038/s41467-024-47312-6] [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: 08/29/2023] [Accepted: 03/27/2024] [Indexed: 04/07/2024] Open
Abstract
Solution-state self-assemblies of block copolymers to form nanostructures are tremendously attractive for their tailorable morphologies and functionalities. While incorporating moieties with strong ordering effects may introduce highly orientational control over the molecular packing and dictate assembly behaviors, subtle and delicate driving forces can yield slower kinetics to reveal manifold metastable morphologies. Herein, we report the unusually convoluted self-assembly behaviors of a liquid crystalline block copolymer bearing triphenylene discotic mesogens. They undergo unusual multiple morphological transitions spontaneously, driven by their intrinsic subtle liquid crystalline ordering effect. Meanwhile, liquid crystalline orderedness can also be built very quickly by doping the mesogens with small-molecule dopants, and the morphological transitions are dramatically accelerated and various exotic micelles are produced. Surprisingly, with high doping levels, the self-assembly mechanism of this block copolymer is completely changed from intramolecular chain shuffling and rearrangement to nucleation-growth mode, based on which self-seeding experiments can be conducted to produce highly uniform fibrils.
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Affiliation(s)
- Huanzhi Yang
- School of Materials Science and Engineering. Beijing Institute of Technology, 100081, Beijing, China
| | - Yunjun Luo
- School of Materials Science and Engineering. Beijing Institute of Technology, 100081, Beijing, China
- Key Laboratory of High Energy Density Materials, MOE. Beijing Institute of Technology, 100081, Beijing, China
| | - Bixin Jin
- School of Materials Science and Engineering. Beijing Institute of Technology, 100081, Beijing, China.
| | - Shumeng Chi
- School of Materials Science and Engineering. Beijing Institute of Technology, 100081, Beijing, China
- Experimental Center of Advanced Materials, Beijing Institute of Technology, 100081, Beijing, China
| | - Xiaoyu Li
- School of Materials Science and Engineering. Beijing Institute of Technology, 100081, Beijing, China.
- Key Laboratory of High Energy Density Materials, MOE. Beijing Institute of Technology, 100081, Beijing, China.
- Experimental Center of Advanced Materials, Beijing Institute of Technology, 100081, Beijing, China.
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5
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Zhang NJ, Lin JX, Chichinadze DV, Wang Y, Watanabe K, Taniguchi T, Fu L, Li JIA. Angle-resolved transport non-reciprocity and spontaneous symmetry breaking in twisted trilayer graphene. NATURE MATERIALS 2024; 23:356-362. [PMID: 38388731 DOI: 10.1038/s41563-024-01809-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 01/16/2024] [Indexed: 02/24/2024]
Abstract
The identification and characterization of spontaneous symmetry breaking is central to our understanding of strongly correlated two-dimensional materials. In this work, we utilize the angle-resolved measurements of transport non-reciprocity to investigate spontaneous symmetry breaking in twisted trilayer graphene. By analysing the angular dependence of non-reciprocity in both longitudinal and transverse channels, we are able to identify the symmetry axis associated with the underlying electronic order. We report that a hysteretic rotation in the mirror axis can be induced by thermal cycles and a large current bias, supporting the spontaneous breaking of rotational symmetry. Moreover, the onset of non-reciprocity with decreasing temperature coincides with the emergence of orbital ferromagnetism. Combined with the angular dependence of the superconducting diode effect, our findings uncover a direct link between rotational and time-reversal symmetry breaking. These symmetry requirements point towards exchange-driven instabilities in momentum space as a possible origin for transport non-reciprocity in twisted trilayer graphene.
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Affiliation(s)
| | - Jiang-Xiazi Lin
- Department of Physics, Brown University, Providence, RI, USA
| | | | - Yibang Wang
- Department of Physics, Brown University, Providence, RI, USA
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Liang Fu
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - J I A Li
- Department of Physics, Brown University, Providence, RI, USA.
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6
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Choi J, Li J, Nag A, Pelliciari J, Robarts H, Tam CC, Walters A, Agrestini S, García-Fernández M, Song D, Eisaki H, Johnston S, Comin R, Ding H, Zhou KJ. Universal Stripe Symmetry of Short-Range Charge Density Waves in Cuprate Superconductors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2307515. [PMID: 37830432 DOI: 10.1002/adma.202307515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/22/2023] [Indexed: 10/14/2023]
Abstract
The omnipresence of charge density waves (CDWs) across almost all cuprate families underpins a common organizing principle. However, a longstanding debate of whether its spatial symmetry is stripe or checkerboard remains unresolved. While CDWs in lanthanum- and yttrium-based cuprates possess a stripe symmetry, distinguishing these two scenarios is challenging for the short-range CDW in bismuth-based cuprates. Here, high-resolution resonant inelastic x-ray scattering is employed to uncover the spatial symmetry of the CDW in Bi2 Sr2 - x Lax CuO6 + δ . Across a wide range of doping and temperature, anisotropic CDW peaks with elliptical shapes are found in reciprocal space. Based on Fourier transform analysis of real-space models, the results are interpreted as evidence of unidirectional charge stripes, hosted by mutually 90°-rotated anisotropic domains. This work paves the way for a unified symmetry and microscopic description of CDW order in cuprates.
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Affiliation(s)
- Jaewon Choi
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Jiemin Li
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, Beijing, 100190, China
| | - Abhishek Nag
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Jonathan Pelliciari
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Hannah Robarts
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
- H. H. Wills Physics Laboratory, University of Bristol, Bristol, BS8 1TL, UK
| | - Charles C Tam
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
- H. H. Wills Physics Laboratory, University of Bristol, Bristol, BS8 1TL, UK
| | - Andrew Walters
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Stefano Agrestini
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | | | - Dongjoon Song
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8560, Japan
- Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Hiroshi Eisaki
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8560, Japan
| | - Steve Johnston
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN, 37996, USA
- Institute for Advanced Materials and Manufacturing, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Riccardo Comin
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Hong Ding
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, Beijing, 100190, China
- Tsung-Dao Lee Institute & School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Ke-Jin Zhou
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire, OX11 0DE, UK
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7
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Libál A, Stepanov S, Reichhardt C, Reichhardt CJO. Dynamic phases and combing effects for elongated particles moving over quenched disorder. SOFT MATTER 2023; 19:7937-7943. [PMID: 37814545 DOI: 10.1039/d3sm01034a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
We consider a two-dimensional system of elongated particles driven over a landscape containing randomly placed pinning sites. For varied pinning site density, external drive magnitude, and particle elongation, we find a wide variety of dynamic phases, including random structures, stripe or combed phases with nematic order, and clogged states. The different regimes can be identified by examining nematic ordering, cluster size, number of pinned particles, and transverse diffusion. In some regimes we find that the pinning can enhance the particle alignment, producing a nonmonotonic signature in the nematic ordering with a maximum at a particular combination of pinning density and drive. The optimal nematic occurs when a sufficient number of particles can be pinned, generating a local shear and leading to what we call a combing effect. At high drives, the combing effect is reduced when the number of pinned particles decreases. For stronger pinning, the particles form a heterogeneous clustered or clogged state that depins into a fluctuating state with high diffusion.
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Affiliation(s)
- A Libál
- Mathematics and Computer Science Department, Babes-Bolyai University, Cluj 400084, Romania
| | - S Stepanov
- Physics Department, Babes-Bolyai University, Cluj 400084, Romania
| | - C Reichhardt
- Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - C J O Reichhardt
- Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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8
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Wårdh J, Granath M, Wu J, Bollinger AT, He X, Božović I. Colossal transverse magnetoresistance due to nematic superconducting phase fluctuations in a copper oxide. PNAS NEXUS 2023; 2:pgad255. [PMID: 37601309 PMCID: PMC10438889 DOI: 10.1093/pnasnexus/pgad255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 07/25/2023] [Indexed: 08/22/2023]
Abstract
Electronic anisotropy ("nematicity") has been detected in cuprate superconductors by various experimental techniques. Using angle-resolved transverse resistance (ARTR) measurements, a very sensitive and background-free technique that can detect 0.5% anisotropy in transport, we have observed it also in La2-xSrxCuO4 (LSCO) for 0.02 ≤ x ≤ 0.25. A central enigma in LSCO is the rotation of the nematic director (orientation of the largest longitudinal resistance) with temperature; this has not been seen before in any material. Here, we address this puzzle by measuring the angle-resolved transverse magnetoresistance (ARTMR) in LSCO. We report the discovery of colossal transverse magnetoresistance (CTMR)-an order-of-magnitude drop in the transverse resistivity in the magnetic field of 6 T. We show that the apparent rotation of the nematic director is caused by anisotropic superconducting fluctuations, which are not aligned with the normal electron fluid, consistent with coexisting bond-aligned and diagonal nematic orders. We quantify this by modeling the (magneto-)conductivity as a sum of normal (Drude) and paraconducting (Aslamazov-Larkin) channels but extended to contain anisotropic Drude and Cooper-pair effective mass tensors. Strikingly, the anisotropy of Cooper-pair stiffness is much larger than that of the normal electrons. It grows dramatically on the underdoped side, where the fluctuations become quasi-one-dimensional. Our analysis is general rather than model dependent. Still, we discuss some candidate microscopic models, including coupled strongly-correlated ladders where the transverse (interladder) phase stiffness is low compared with the longitudinal intraladder stiffness, as well as the anisotropic superconducting fluctuations expected close to the transition to a pair-density wave state.
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Affiliation(s)
- Jonatan Wårdh
- Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden
| | - Mats Granath
- Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden
| | - Jie Wu
- Brookhaven National Laboratory, Upton, NY 11973, USA
- Present address: School of Science, Westlake University, Hangzhou, China
| | | | - Xi He
- Department of Chemistry, Yale University, New Haven, CT 06520, USA
- Energy Sciences Institute, Yale University, West Haven, CT 06516, USA
| | - Ivan Božović
- Brookhaven National Laboratory, Upton, NY 11973, USA
- Department of Chemistry, Yale University, New Haven, CT 06520, USA
- Energy Sciences Institute, Yale University, West Haven, CT 06516, USA
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9
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Wang W, Li J, Liang Z, Wu L, Lozano PM, Komarek AC, Shen X, Reid AH, Wang X, Li Q, Yin W, Sun K, Robinson IK, Zhu Y, Dean MP, Tao J. Verwey transition as evolution from electronic nematicity to trimerons via electron-phonon coupling. SCIENCE ADVANCES 2023; 9:eadf8220. [PMID: 37294769 PMCID: PMC10256157 DOI: 10.1126/sciadv.adf8220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 05/04/2023] [Indexed: 06/11/2023]
Abstract
Understanding the driving mechanisms behind metal-insulator transitions (MITs) is a critical step toward controlling material's properties. Since the proposal of charge order-induced MIT in magnetite Fe3O4 in 1939 by Verwey, the nature of the charge order and its role in the transition have remained elusive. Recently, a trimeron order was found in the low-temperature structure of Fe3O4; however, the expected transition entropy change in forming trimeron is greater than the observed value, which arises a reexamination of the ground state in the high-temperature phase. Here, we use electron diffraction to unveil that a nematic charge order on particular Fe sites emerges in the high-temperature structure of bulk Fe3O4 and that, upon cooling, a competitive intertwining of charge and lattice orders arouses the Verwey transition. Our findings discover an unconventional type of electronic nematicity in correlated materials and offer innovative insights into the transition mechanism in Fe3O4 via the electron-phonon coupling.
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Affiliation(s)
- Wei Wang
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jun Li
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Zhixiu Liang
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Lijun Wu
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Pedro M. Lozano
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
| | - Alexander C. Komarek
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Street 40, 01187 Dresden, Germany
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Alex H. Reid
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Qiang Li
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
| | - Weiguo Yin
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Kai Sun
- Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ian K. Robinson
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
- London Centre for Nanotechnology, University College, London WC1E 6BT, UK
| | - Yimei Zhu
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Mark P.M. Dean
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jing Tao
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY 11973, USA
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10
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Guo Y, Qiu D, Shao M, Song J, Wang Y, Xu M, Yang C, Li P, Liu H, Xiong J. Modulations in Superconductors: Probes of Underlying Physics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209457. [PMID: 36504310 DOI: 10.1002/adma.202209457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/16/2022] [Indexed: 06/02/2023]
Abstract
The importance of modulations is elevated to an unprecedented level, due to the delicate conditions required to bring out exotic phenomena in quantum materials, such as topological materials, magnetic materials, and superconductors. Recently, state-of-the-art modulation techniques in material science, such as electric-double-layer transistor, piezoelectric-based strain apparatus, angle twisting, and nanofabrication, have been utilized in superconductors. They not only efficiently increase the tuning capability to the broader ranges but also extend the tuning dimensionality to unprecedented degrees of freedom, including quantum fluctuations of competing phases, electronic correlation, and phase coherence essential to global superconductivity. Here, for a comprehensive review, these techniques together with the established modulation methods, such as elemental substitution, annealing, and polarization-induced gating, are contextualized. Depending on the mechanism of each method, the modulations are categorized into stoichiometric manipulation, electrostatic gating, mechanical modulation, and geometrical design. Their recent advances are highlighted by applications in newly discovered superconductors, e.g., nickelates, Kagome metals, and magic-angle graphene. Overall, the review is to provide systematic modulations in emergent superconductors and serve as the coordinate for future investigations, which can stimulate researchers in superconductivity and other fields to perform various modulations toward a thorough understanding of quantum materials.
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Affiliation(s)
- Yehao Guo
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Dong Qiu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Mingxin Shao
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Jingyan Song
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Yang Wang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Minyi Xu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Chao Yang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Peng Li
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Haiwen Liu
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Jie Xiong
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
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11
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Song CL, Main EJ, Simmons F, Liu S, Phillabaum B, Dahmen KA, Hudson EW, Hoffman JE, Carlson EW. Critical nematic correlations throughout the superconducting doping range in Bi 2-zPb zSr 2-yLa yCuO 6+x. Nat Commun 2023; 14:2622. [PMID: 37147296 PMCID: PMC10162959 DOI: 10.1038/s41467-023-38249-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/17/2023] [Indexed: 05/07/2023] Open
Abstract
Charge modulations have been widely observed in cuprates, suggesting their centrality for understanding the high-Tc superconductivity in these materials. However, the dimensionality of these modulations remains controversial, including whether their wavevector is unidirectional or bidirectional, and also whether they extend seamlessly from the surface of the material into the bulk. Material disorder presents severe challenges to understanding the charge modulations through bulk scattering techniques. We use a local technique, scanning tunneling microscopy, to image the static charge modulations on Bi2-zPbzSr2-yLayCuO6+x. The ratio of the phase correlation length ξCDW to the orientation correlation length ξorient points to unidirectional charge modulations. By computing new critical exponents at free surfaces including that of the pair connectivity correlation function, we show that these locally 1D charge modulations are actually a bulk effect resulting from classical 3D criticality of the random field Ising model throughout the entire superconducting doping range.
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Affiliation(s)
- Can-Li Song
- Department of Physics, Harvard University, Cambridge, MA, 02138, USA
| | - Elizabeth J Main
- Department of Physics, Harvard University, Cambridge, MA, 02138, USA
| | - Forrest Simmons
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
- Purdue Quantum Science and Engineering Institute, West Lafayette, IN, 47907, USA
| | - Shuo Liu
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - Benjamin Phillabaum
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - Karin A Dahmen
- Department of Physics, University of Illinois, Urbana-Champaign, IL, 61801, USA
| | - Eric W Hudson
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | | | - Erica W Carlson
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA.
- Purdue Quantum Science and Engineering Institute, West Lafayette, IN, 47907, USA.
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12
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Lee J, Park JW, Cho GY, Yeom HW. Mobile Kink Solitons in a Van der Waals Charge-Density-Wave Layer. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2300160. [PMID: 37058741 DOI: 10.1002/adma.202300160] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/18/2023] [Indexed: 06/04/2023]
Abstract
Kinks, point-like geometrical defects along dislocations, domain walls, and DNA, are stable and mobile, as solutions of a sine-Gordon wave equation. While they are widely investigated for crystal deformations and domain wall motions, electronic properties of individual kinks have received little attention. In this work, electronically and topologically distinct kinks are discovered along electronic domain walls in a correlated van der Waals insulator of 1T-TaS2 . Mobile kinks and antikinks are identified as trapped by pinning defects and imaged in scanning tunneling microscopy. Their atomic structures and in-gap electronic states are unveiled, which are mapped approximately into Su-Schrieffer-Heeger solitons. The twelvefold degeneracy of the domain walls in the present system guarantees an extraordinarily large number of distinct kinks and antikinks to emerge. Such large degeneracy together with the robust geometrical nature may be useful for handling multilevel information in van der Waals materials architectures.
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Affiliation(s)
- Jinwon Lee
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 37673, Pohang, Republic of Korea
- Department of Physics, Pohang University of Science and Technology, 37673, Pohang, Republic of Korea
- Leiden Institute of Physics, Leiden University, 2333 CA, Leiden, The Netherlands
| | - Jae Whan Park
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 37673, Pohang, Republic of Korea
| | - Gil Young Cho
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 37673, Pohang, Republic of Korea
- Department of Physics, Pohang University of Science and Technology, 37673, Pohang, Republic of Korea
| | - Han Woong Yeom
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 37673, Pohang, Republic of Korea
- Department of Physics, Pohang University of Science and Technology, 37673, Pohang, Republic of Korea
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13
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Adamus P, Xu B, Marsik P, Dubroka A, Barabasová P, Růžičková H, Puphal P, Pomjakushina E, Tallon JL, Mathis YL, Munzar D, Bernhard C. Analogies of phonon anomalies and electronic gap features in the infrared response of Sr14-xCa xCu 24O 41and underdoped YBa 2Cu 3O6+x. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 86:044502. [PMID: 36821858 DOI: 10.1088/1361-6633/acbe4f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
We present an experimental and theoretical study which compares the phonon anomalies and the electronic gap features in the infrared response of the weakly coupled two-leg-ladders in Sr14-xCaxCu24O41(SCCO) with those of the underdoped high-Tcsuperconductor YBa2Cu3O6+x(YBCO) and thereby reveals some surprising analogies. Specifically, we present a phenomenological model that describes the anomalous doping- and temperature-dependence of some of the phonon features in thea-axis response (field along the rungs of the ladders) of SCCO. It assumes that the phonons are coupled to charge oscillations within the ladders. Their changes with decreasing temperature reveal the formation of a crystal (density wave) of hole pairs that are oriented along the rungs. We also discuss the analogy to a similar model that was previously used to explain the phonon anomalies and an electronic plasma mode in thec-axis response (field perpendicular to the CuO2planes) of YBCO. We further confirm that an insulator-like pseudogap develops in thea-axis conductivity of SCCO which closely resembles that in thec-axis conductivity of YBCO. Most surprisingly, we find that thec-axis conductivity (field along the legs of the ladders) of SCCO is strikingly similar to the in-plane one (field parallel to the CuO2planes) of YBCO. Notably, in both cases a dip feature develops in the normal state spectra that is connected with a spectral weight shift toward low frequencies and can thus be associated with precursor superconducting pairing correlations that are lacking macroscopic phase coherence. This SCCO-YBCO analogy indicates that collective degrees of freedom contribute to the low-energy response of underdoped highTccuprates and it even suggests that the charges in the CuO2planes tend to segregate forming quasi-one-dimensional structures similar to the two-leg ladders, as predicted for the stripe-scenario or certain intertwinned states.
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Affiliation(s)
- Petr Adamus
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Bing Xu
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Premysl Marsik
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - Adam Dubroka
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Paulína Barabasová
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Hana Růžičková
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Pascal Puphal
- Laboratory for Multiscale Materials Experiments, PSI, 5232 Villigen, Switzerland
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | | | - Jeffery L Tallon
- Victoria University of Wellington, Robinson Research Institute, POB 33436, Lower Hutt 5046, New Zealand
| | - Yves-Laurent Mathis
- Karlsruhe Institute of Technology, Institute for Beam Physics and Technology, Hermann-von-Helmhotz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Dominik Munzar
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Christian Bernhard
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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14
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Jiang K, Wu T, Yin JX, Wang Z, Hasan MZ, Wilson SD, Chen X, Hu J. Kagome superconductors AV 3Sb 5 (A = K, Rb, Cs). Natl Sci Rev 2023; 10:nwac199. [PMID: 36935933 PMCID: PMC10016199 DOI: 10.1093/nsr/nwac199] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/20/2022] [Accepted: 02/14/2022] [Indexed: 11/14/2022] Open
Abstract
The quasi-two-dimensional kagome materials AV3Sb5 (A = K, Rb, Cs) were found to be a prime example of kagome superconductors, a new quantum platform to investigate the interplay between electron correlation effects, topology and geometric frustration. In this review, we report recent progress on the experimental and theoretical studies of AV3Sb5 and provide a broad picture of this fast-developing field in order to stimulate an expanded search for unconventional kagome superconductors. We review the electronic properties of AV3Sb5, the experimental measurements of the charge density wave state, evidence of time-reversal symmetry breaking and other potential hidden symmetry breaking in these materials. A variety of theoretical proposals and models that address the nature of the time-reversal symmetry breaking are discussed. Finally, we review the superconducting properties of AV3Sb5, especially the potential pairing symmetries and the interplay between superconductivity and the charge density wave state.
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Affiliation(s)
- Kun Jiang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Tao Wu
- Corresponding author. E-mail:
| | | | - Zhenyu Wang
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ 08544, USA
| | - Stephen D Wilson
- Materials Department and California Nanosystems Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
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15
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Melting of generalized Wigner crystals in transition metal dichalcogenide heterobilayer Moiré systems. Nat Commun 2022; 13:7098. [PMID: 36402757 PMCID: PMC9675862 DOI: 10.1038/s41467-022-34683-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 10/18/2022] [Indexed: 11/21/2022] Open
Abstract
Moiré superlattice systems such as transition metal dichalcogenide heterobilayers have garnered significant recent interest due to their promising utility as tunable solid state simulators. Recent experiments on a WSe2/WS2 heterobilayer detected incompressible charge ordered states that one can view as generalized Wigner crystals. The tunability of the transition metal dichalcogenide heterobilayer Moiré system presents an opportunity to study the rich set of possible phases upon melting these charge-ordered states. Here we use Monte Carlo simulations to study these intermediate phases in between incompressible charge-ordered states in the strong coupling limit. We find two distinct stripe solid states to be each preceded by distinct types of nematic states. In particular, we discover microscopic mechanisms that stabilize each of the nematic states, whose order parameter transforms as the two-dimensional E representation of the Moiré lattice point group. Our results provide a testable experimental prediction of where both types of nematic occur, and elucidate the microscopic mechanism driving their formation.
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16
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Mak KF, Shan J. Semiconductor moiré materials. NATURE NANOTECHNOLOGY 2022; 17:686-695. [PMID: 35836003 DOI: 10.1038/s41565-022-01165-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
Moiré materials have emerged as a platform for exploring the physics of strong electronic correlations and non-trivial band topology. Here we review the recent progress in semiconductor moiré materials, with a particular focus on transition metal dichalcogenides. Following a brief overview of the general features in this class of materials, we discuss recent theoretical and experimental studies on Hubbard physics, Kane-Mele-Hubbard physics and equilibrium moiré excitons. We also comment on the future opportunities and challenges in the studies of transition metal dichalcogenide and other semiconductor moiré materials.
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Affiliation(s)
- Kin Fai Mak
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, USA.
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, USA.
| | - Jie Shan
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, USA.
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, USA.
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17
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Xie T, Liu Z, Gu Y, Gong D, Mao H, Liu J, Hu C, Ma X, Yao Y, Zhao L, Zhou X, Schneeloch J, Gu G, Danilkin S, Yang YF, Luo H, Li S. Tracking the nematicity in cuprate superconductors: a resistivity study under uniaxial pressure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:334001. [PMID: 35671749 DOI: 10.1088/1361-648x/ac768c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/07/2022] [Indexed: 06/15/2023]
Abstract
Overshadowing the superconducting dome in hole-doped cuprates, the pseudogap state is still one of the mysteries that no consensus can be achieved. It has been suggested that the rotational symmetry is broken in this state and may result in a nematic phase transition, whose temperature seems to coincide with the onset temperature of the pseudogap stateT∗around optimal doping level, raising the question whether the pseudogap results from the establishment of the nematic order. Here we report results of resistivity measurements under uniaxial pressure on several hole-doped cuprates, where the normalized slope of the elastoresistivityζcan be obtained as illustrated in iron-based superconductors. The temperature dependence ofζalong particular lattice axis exhibits kink feature atTkand shows Curie-Weiss-like behavior above it, which may suggest a spontaneous nematic transition. WhileTkseems to be the same asT∗around the optimal doping and in the overdoped region, they become very different in underdoped La2-xSrxCuO4. Our results suggest that the nematic order, if indeed existing, is an electronic phase within the pseudogap state.
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Affiliation(s)
- Tao Xie
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - Zhaoyu Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Yanhong Gu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Dongliang Gong
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Huican Mao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Jing Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Cheng Hu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Xiaoyan Ma
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Yuan Yao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Lin Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Xingjiang Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - John Schneeloch
- Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Genda Gu
- Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Sergey Danilkin
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, Lucas Heights, NSW 2234, Australia
| | - Yi-Feng Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Huiqian Luo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Shiliang Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
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18
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Uchida J, Soberats B, Gupta M, Kato T. Advanced Functional Liquid Crystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2109063. [PMID: 35034382 DOI: 10.1002/adma.202109063] [Citation(s) in RCA: 65] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/21/2021] [Indexed: 06/14/2023]
Abstract
Liquid crystals have been intensively studied as functional materials. Recently, integration of various disciplines has led to new directions in the design of functional liquid-crystalline materials in the fields of energy, water, photonics, actuation, sensing, and biotechnology. Here, recent advances in functional liquid crystals based on polymers, supramolecular complexes, gels, colloids, and inorganic-based hybrids are reviewed, from design strategies to functionalization of these materials and interfaces. New insights into liquid crystals provided by significant progress in advanced measurements and computational simulations, which enhance new design and functionalization of liquid-crystalline materials, are also discussed.
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Affiliation(s)
- Junya Uchida
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Bartolome Soberats
- Department of Chemistry, University of the Balearic Islands, Cra. Valldemossa Km. 7.5, Palma de Mallorca, 07122, Spain
| | - Monika Gupta
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Takashi Kato
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
- Research Initiative for Supra-Materials, Shinshu University, Wakasato, Nagano, 380-8553, Japan
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19
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Poojitha B, Shaji A, Badola S, Saha S. Spin–phonon coupling in ferrimagnet spinel CoMn 2O 4. J Chem Phys 2022; 156:184701. [DOI: 10.1063/5.0087770] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Coupling of material properties provides new fundamental insights and possibilities toward multifunctional devices. The spinel structures display strong coupling between different order parameters, as a consequence, exhibiting many fascinating properties, such as multiferroicity and superconductivity. Here, we have investigated the structural, magnetic, and vibrational properties of mixed-spinel CoMn2O4 stabilized in distorted tetragonal structures as evidenced from x-ray diffraction measurements. Magnetization measurements reveal two ferrimagnetic phase transitions at 185 and 90 K. Raman scattering measurements reveal the renormalization of phonon parameters for a few phonon modes at low temperatures, arising from spin–phonon coupling. The obtained value for λS2 is ∼2 cm−1. The strength of spin–phonon coupling ( λ) is estimated according to the spins involved in the corresponding lattice vibrations and discussed.
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Affiliation(s)
- Bommareddy Poojitha
- Department of Physics, Indian Institute of Science Education and Research, Bhopal 462066, India
| | - Aswin Shaji
- Department of Physics, Indian Institute of Science Education and Research, Bhopal 462066, India
| | - Shalini Badola
- Department of Physics, Indian Institute of Science Education and Research, Bhopal 462066, India
| | - Surajit Saha
- Department of Physics, Indian Institute of Science Education and Research, Bhopal 462066, India
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20
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Zhang S, Zhang P, Chern GW. Anomalous phase separation in a correlated electron system: Machine-learning-enabled large-scale kinetic Monte Carlo simulations. Proc Natl Acad Sci U S A 2022; 119:e2119957119. [PMID: 35486688 PMCID: PMC9170136 DOI: 10.1073/pnas.2119957119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 03/25/2022] [Indexed: 11/18/2022] Open
Abstract
SignificancePhase separation is crucial to the functionalities of many correlated electron materials with notable examples including colossal magnetoresistance in manganites and high-Tc superconductivity in cuprates. However, the nonequilibrium phase-separation dynamics in such systems are poorly understood theoretically, partly because the required multiscale modeling is computationally very demanding. With the aid of machine-learning methods, we have achieved large-scale dynamical simulations in a representative correlated electron system. We observe an unusual relaxation process that is beyond the framework of classical phase-ordering theories. We also uncover a correlation-induced freezing behavior, which could be a generic feature of phase separation in correlated electron systems.
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Affiliation(s)
- Sheng Zhang
- Department of Physics, University of Virginia, Charlottesville, VA 22904
| | - Puhan Zhang
- Department of Physics, University of Virginia, Charlottesville, VA 22904
| | - Gia-Wei Chern
- Department of Physics, University of Virginia, Charlottesville, VA 22904
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21
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Delacrétaz LV, Goutéraux B, Ziogas V. Damping of Pseudo-Goldstone Fields. PHYSICAL REVIEW LETTERS 2022; 128:141601. [PMID: 35476470 DOI: 10.1103/physrevlett.128.141601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Approximate symmetries abound in nature. If these symmetries are also spontaneously broken, the would-be Goldstone modes acquire a small mass, or inverse correlation length, and are referred to as pseudo-Goldstones. At nonzero temperature, the effects of dissipation can be captured by hydrodynamics at sufficiently long scales compared to the local equilibrium. Here, we show that, in the limit of weak explicit breaking, locality of hydrodynamics implies that the damping of pseudo-Goldstones is completely determined by their mass and diffusive transport coefficients. We present many applications: superfluids, QCD in the chiral limit, Wigner crystal and density wave phases in the presence of an external magnetic field or not, nematic phases, and (anti)ferromagnets. For electronic density wave phases, pseudo-Goldstone damping generates a contribution to the resistivity independent of the strength of disorder, which can have a linear temperature dependence provided the associated diffusivity saturates a bound. This is reminiscent of the phenomenology of strange metal high-T_{c} superconductors, where charge density waves are observed across the phase diagram.
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Affiliation(s)
- Luca V Delacrétaz
- Kadanoff Center for Theoretical Physics, University of Chicago, Chicago, Illinois 60637, USA
| | - Blaise Goutéraux
- CPHT, CNRS, École Polytechnique, IP Paris, F-91128 Palaiseau, France
| | - Vaios Ziogas
- CPHT, CNRS, École Polytechnique, IP Paris, F-91128 Palaiseau, France
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22
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Uniaxial pressure induced stripe order rotation in La1.88Sr0.12CuO4. Nat Commun 2022; 13:1795. [PMID: 35379813 PMCID: PMC8979978 DOI: 10.1038/s41467-022-29465-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 03/16/2022] [Indexed: 11/08/2022] Open
Abstract
AbstractStatic stripe order is detrimental to superconductivity. Yet, it has been proposed that transverse stripe fluctuations may enhance the inter-stripe Josephson coupling and thus promote superconductivity. Direct experimental studies of stripe dynamics, however, remain difficult. From a strong-coupling perspective, transverse stripe fluctuations are realized in the form of dynamic “kinks”—sideways shifting stripe sections. Here, we show how modest uniaxial pressure tuning reorganizes directional kink alignment. Our starting point is La1.88Sr0.12CuO4 where transverse kink ordering results in a rotation of stripe order away from the crystal axis. Application of mild uniaxial pressure changes the ordering pattern and pins the stripe order to the crystal axis. This reordering occurs at a much weaker pressure than that to detwin the stripe domains and suggests a rather weak transverse stripe stiffness. Weak spatial stiffness and transverse quantum fluctuations are likely key prerequisites for stripes to coexist with superconductivity.
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23
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Jang H, Song S, Kihara T, Liu Y, Lee SJ, Park SY, Kim M, Kim HD, Coslovich G, Nakata S, Kubota Y, Inoue I, Tamasaku K, Yabashi M, Lee H, Song C, Nojiri H, Keimer B, Kao CC, Lee JS. Characterization of photoinduced normal state through charge density wave in superconducting YBa 2Cu 3O 6.67. SCIENCE ADVANCES 2022; 8:eabk0832. [PMID: 35138893 PMCID: PMC8827649 DOI: 10.1126/sciadv.abk0832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
The normal state of high-Tc cuprates has been considered one of the essential topics in high-temperature superconductivity research. However, compared to the high magnetic field study of it, understanding a photoinduced normal state remains elusive. Here, we explore a photoinduced normal state of YBa2Cu3O6.67 through a charge density wave (CDW) with time-resolved resonant soft x-ray scattering, as well as a high magnetic field x-ray scattering. In the nonequilibrium state where people predict a quenched superconducting state based on the previous optical spectroscopies, we experimentally observed a similar analogy to the competition between superconductivity and CDW shown in the equilibrium state. We further observe that the broken pairing states in the superconducting CuO2 plane via the optical pump lead to nucleation of three-dimensional CDW precursor correlation. Ultimately, these findings provide a critical clue that the characteristics of the photoinduced normal state show a solid resemblance to those under magnetic fields in equilibrium conditions.
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Affiliation(s)
- Hoyoung Jang
- PAL-XFEL, Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
- Photon Science Center, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Sanghoon Song
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Takumi Kihara
- Institute for Materials Research, Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan
| | - Yijin Liu
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Sang-Jun Lee
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Sang-Youn Park
- PAL-XFEL, Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Minseok Kim
- PAL-XFEL, Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Hyeong-Do Kim
- PAL-XFEL, Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Giacomo Coslovich
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Suguru Nakata
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - Yuya Kubota
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, Sayo, Hyogo, 679-5198, Japan
| | - Ichiro Inoue
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | | | - Makina Yabashi
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, Sayo, Hyogo, 679-5198, Japan
| | - Heemin Lee
- Departments of Physics, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Changyong Song
- Photon Science Center, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
- Departments of Physics, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Hiroyuki Nojiri
- Institute for Materials Research, Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan
| | - Bernhard Keimer
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - Chi-Chang Kao
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Jun-Sik Lee
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
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24
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Topological Doping and Superconductivity in Cuprates: An Experimental Perspective. Symmetry (Basel) 2021. [DOI: 10.3390/sym13122365] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Hole doping into a correlated antiferromagnet leads to topological stripe correlations, involving charge stripes that separate antiferromagnetic spin stripes of opposite phases. The topological spin stripe order causes the spin degrees of freedom within the charge stripes to feel a geometric frustration with their environment. In the case of cuprates, where the charge stripes have the character of a hole-doped two-leg spin ladder, with corresponding pairing correlations, anti-phase Josephson coupling across the spin stripes can lead to a pair-density-wave order in which the broken translation symmetry of the superconducting wave function is accommodated by pairs with finite momentum. This scenario is now experimentally verified by recently reported measurements on La2−xBaxCuO4 with x=1/8. While pair-density-wave order is not common as a cuprate ground state, it provides a basis for understanding the uniform d-wave order that is more typical in superconducting cuprates.
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25
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Chen H, Yang H, Hu B, Zhao Z, Yuan J, Xing Y, Qian G, Huang Z, Li G, Ye Y, Ma S, Ni S, Zhang H, Yin Q, Gong C, Tu Z, Lei H, Tan H, Zhou S, Shen C, Dong X, Yan B, Wang Z, Gao HJ. Roton pair density wave in a strong-coupling kagome superconductor. Nature 2021; 599:222-228. [PMID: 34587621 DOI: 10.1038/s41586-021-03983-5] [Citation(s) in RCA: 103] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 09/01/2021] [Indexed: 02/08/2023]
Abstract
The transition metal kagome lattice materials host frustrated, correlated and topological quantum states of matter1-9. Recently, a new family of vanadium-based kagome metals, AV3Sb5 (A = K, Rb or Cs), with topological band structures has been discovered10,11. These layered compounds are nonmagnetic and undergo charge density wave transitions before developing superconductivity at low temperatures11-19. Here we report the observation of unconventional superconductivity and a pair density wave (PDW) in CsV3Sb5 using scanning tunnelling microscope/spectroscopy and Josephson scanning tunnelling spectroscopy. We find that CsV3Sb5 exhibits a V-shaped pairing gap Δ ~ 0.5 meV and is a strong-coupling superconductor (2Δ/kBTc ~ 5) that coexists with 4a0 unidirectional and 2a0 × 2a0 charge order. Remarkably, we discover a 3Q PDW accompanied by bidirectional 4a0/3 spatial modulations of the superconducting gap, coherence peak and gap depth in the tunnelling conductance. We term this novel quantum state a roton PDW associated with an underlying vortex-antivortex lattice that can account for the observed conductance modulations. Probing the electronic states in the vortex halo in an applied magnetic field, in strong field that suppresses superconductivity and in zero field above Tc, reveals that the PDW is a primary state responsible for an emergent pseudogap and intertwined electronic order. Our findings show striking analogies and distinctions to the phenomenology of high-Tc cuprate superconductors, and provide groundwork for understanding the microscopic origin of correlated electronic states and superconductivity in vanadium-based kagome metals.
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Affiliation(s)
- Hui Chen
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,Songshan Lake Materials Laboratory, Dongguan, People's Republic of China
| | - Haitao Yang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,Songshan Lake Materials Laboratory, Dongguan, People's Republic of China
| | - Bin Hu
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Zhen Zhao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Jie Yuan
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Yuqing Xing
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Guojian Qian
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Zihao Huang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Geng Li
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Yuhan Ye
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Sheng Ma
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Shunli Ni
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Hua Zhang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Qiangwei Yin
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing, People's Republic of China
| | - Chunsheng Gong
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing, People's Republic of China
| | - Zhijun Tu
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing, People's Republic of China
| | - Hechang Lei
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing, People's Republic of China
| | - Hengxin Tan
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Sen Zhou
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, People's Republic of China.,CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Chengmin Shen
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Xiaoli Dong
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Binghai Yan
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Ziqiang Wang
- Department of Physics, Boston College, Chestnut Hill, MA, USA.
| | - Hong-Jun Gao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China. .,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People's Republic of China. .,CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, People's Republic of China. .,Songshan Lake Materials Laboratory, Dongguan, People's Republic of China.
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26
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Choi H, Vinograd I, Chaffey C, Curro NJ. Inverse Laplace transformation analysis of stretched exponential relaxation. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 331:107050. [PMID: 34507236 DOI: 10.1016/j.jmr.2021.107050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 08/05/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
We investigate the effectiveness of the Inverse Laplace Transform (ILT) analysis method to extract the distribution of relaxation rates from nuclear magnetic resonance data with stretched exponential relaxation. Stretched-relaxation is a hallmark of a distribution of relaxation rates, and an analytical expression exists for this distribution for the case of a spin-1/2 nucleus. We compare this theoretical distribution with those extracted via the ILT method for several values of the stretching exponent and at different levels of experimental noise. The ILT accurately captures the distributions for β≲0.7, and for signal to noise ratios greater than ∼40; however the ILT distributions tend to introduce artificial oscillatory components. We further use the ILT approach to analyze stretched relaxation for spin I>1/2 and find that the distributions are accurately captured by the theoretical expression for I=1/2. Our results provide a solid foundation to interpret distributions of relaxation rates for general spin I in terms of stretched exponential fits.
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Affiliation(s)
- H Choi
- College of Nanoscale Science and Engineering, State University of New York Polytechnic Institute, New York 12203, USA.
| | - I Vinograd
- Department of Physics, University of California, Davis, CA 95616, USA
| | - C Chaffey
- Department of Physics, University of California, Davis, CA 95616, USA
| | - N J Curro
- Department of Physics, University of California, Davis, CA 95616, USA.
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27
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Negi D, Singh D, Ahuja R, van Aken PA. Coexisting commensurate and incommensurate charge ordered phases in CoO. Sci Rep 2021; 11:19415. [PMID: 34593883 PMCID: PMC8484683 DOI: 10.1038/s41598-021-98739-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/13/2021] [Indexed: 02/08/2023] Open
Abstract
The subtle interplay of strong electronic correlations in a distorted crystal lattice often leads to the evolution of novel emergent functionalities in the strongly correlated materials (SCM). Here, we unravel such unprecedented commensurate (COM) and incommensurate (ICOM) charge ordered (CO) phases at room temperature in a simple transition-metal mono-oxide, namely CoO. The electron diffraction pattern unveils a COM ([Formula: see text]=[Formula: see text] and ICOM ([Formula: see text]) periodic lattice distortion. Transmission electron microscopy (TEM) captures unidirectional and bidirectional stripe patterns of charge density modulations. The widespread phase singularities in the phase-field of the order parameter (OP) affirms the abundant topological disorder. Using, density functional theory (DFT) calculations, we demystify the underlying electronic mechanism. The DFT study shows that a cation disordering ([Formula: see text]) stabilizes Jahn-Teller (JT) distortion and localized aliovalent [Formula: see text] states in CoO. Therefore, the lattice distortion accompanied with mixed valence states ([Formula: see text]) states introduces CO in CoO. Our findings offer an electronic paradigm to engineer CO to exploit the associated electronic functionalities in widely available transition-metal mono-oxides.
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Affiliation(s)
- Devendra Negi
- Stuttgart Center for Electron Microscopy, Max Planck Institute for Solid State Research, Heisenbergstr.1, 70569, Stuttgart, Germany.
| | - Deobrat Singh
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden
| | - Rajeev Ahuja
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar, Punjab, 140001, India
| | - Peter A van Aken
- Stuttgart Center for Electron Microscopy, Max Planck Institute for Solid State Research, Heisenbergstr.1, 70569, Stuttgart, Germany
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28
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Vanishing nematic order beyond the pseudogap phase in overdoped cuprate superconductors. Proc Natl Acad Sci U S A 2021; 118:2106881118. [PMID: 34413195 DOI: 10.1073/pnas.2106881118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During the last decade, translational and rotational symmetry-breaking phases-density wave order and electronic nematicity-have been established as generic and distinct features of many correlated electron systems, including pnictide and cuprate superconductors. However, in cuprates, the relationship between these electronic symmetry-breaking phases and the enigmatic pseudogap phase remains unclear. Here, we employ resonant X-ray scattering in a cuprate high-temperature superconductor [Formula: see text] (Nd-LSCO) to navigate the cuprate phase diagram, probing the relationship between electronic nematicity of the Cu 3d orbitals, charge order, and the pseudogap phase as a function of doping. We find evidence for a considerable decrease in electronic nematicity beyond the pseudogap phase, either by raising the temperature through the pseudogap onset temperature T* or increasing doping through the pseudogap critical point, p*. These results establish a clear link between electronic nematicity, the pseudogap, and its associated quantum criticality in overdoped cuprates. Our findings anticipate that electronic nematicity may play a larger role in understanding the cuprate phase diagram than previously recognized, possibly having a crucial role in the phenomenology of the pseudogap phase.
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29
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Wiecki P, Frachet M, Haghighirad AA, Wolf T, Meingast C, Heid R, Böhmer AE. Emerging symmetric strain response and weakening nematic fluctuations in strongly hole-doped iron-based superconductors. Nat Commun 2021; 12:4824. [PMID: 34376670 PMCID: PMC8355183 DOI: 10.1038/s41467-021-25121-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 07/25/2021] [Indexed: 11/18/2022] Open
Abstract
Electronic nematicity is often found in unconventional superconductors, suggesting its relevance for electronic pairing. In the strongly hole-doped iron-based superconductors, the symmetry channel and strength of the nematic fluctuations, as well as the possible presence of long-range nematic order, remain controversial. Here, we address these questions using transport measurements under elastic strain. By decomposing the strain response into the appropriate symmetry channels, we demonstrate the emergence of a giant in-plane symmetric contribution, associated with the growth of both strong electronic correlations and the sensitivity of these correlations to strain. We find weakened remnants of the nematic fluctuations that are present at optimal doping, but no change in the symmetry channel of nematic fluctuations with hole doping. Furthermore, we find no indication of a nematic-ordered state in the AFe2As2 (A = K, Rb, Cs) superconductors. These results revise the current understanding of nematicity in hole-doped iron-based superconductors.
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Affiliation(s)
- P Wiecki
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany
| | - M Frachet
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany
| | - A-A Haghighirad
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany
| | - T Wolf
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany
| | - C Meingast
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany
| | - R Heid
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany
| | - A E Böhmer
- Karlsruhe Institute of Technology, Institute for Quantum Materials and Technologies, Karlsruhe, Germany.
- Institut für Experimentalphysik IV, Ruhr-Universität Bochum, Bochum, Germany.
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30
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Jin C, Tao Z, Li T, Xu Y, Tang Y, Zhu J, Liu S, Watanabe K, Taniguchi T, Hone JC, Fu L, Shan J, Mak KF. Stripe phases in WSe 2/WS 2 moiré superlattices. NATURE MATERIALS 2021; 20:940-944. [PMID: 33767398 DOI: 10.1038/s41563-021-00959-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 02/12/2021] [Indexed: 06/12/2023]
Abstract
Stripe phases, in which the rotational symmetry of charge density is spontaneously broken, occur in many strongly correlated systems with competing interactions1-11. However, identifying and studying such stripe phases remains challenging. Here we uncover stripe phases in WSe2/WS2 moiré superlattices by combining optical anisotropy and electronic compressibility measurements. We find strong electronic anisotropy over a large doping range peaked at 1/2 filling of the moiré superlattice. The 1/2 state is incompressible and assigned to an insulating stripe crystal phase. Wide-field imaging reveals domain configurations with a preferential alignment along the high-symmetry axes of the moiré superlattice. Away from 1/2 filling, we observe additional stripe crystals at commensurate filling 1/4, 2/5 and 3/5, and compressible electronic liquid crystal states at incommensurate fillings. Our results demonstrate that two-dimensional semiconductor moiré superlattices are a highly tunable platform from which to study the stripe phases and their interplay with other symmetry breaking ground states.
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Affiliation(s)
- Chenhao Jin
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, USA.
| | - Zui Tao
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, USA
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Tingxin Li
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Yang Xu
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Yanhao Tang
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Jiacheng Zhu
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Song Liu
- Department of Mechanical Engineering, Columbia University, New York, NY, USA
| | - Kenji Watanabe
- National Institute for Materials Science, Tsukuba, Japan
| | | | - James C Hone
- Department of Mechanical Engineering, Columbia University, New York, NY, USA
| | - Liang Fu
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Jie Shan
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, USA.
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, USA.
| | - Kin Fai Mak
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, USA.
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, USA.
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31
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Shen Y, Fabbris G, Miao H, Cao Y, Meyers D, Mazzone DG, Assefa TA, Chen XM, Kisslinger K, Prabhakaran D, Boothroyd AT, Tranquada JM, Hu W, Barbour AM, Wilkins SB, Mazzoli C, Robinson IK, Dean MPM. Charge Condensation and Lattice Coupling Drives Stripe Formation in Nickelates. PHYSICAL REVIEW LETTERS 2021; 126:177601. [PMID: 33988428 DOI: 10.1103/physrevlett.126.177601] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 03/31/2021] [Indexed: 06/12/2023]
Abstract
Revealing the predominant driving force behind symmetry breaking in correlated materials is sometimes a formidable task due to the intertwined nature of different degrees of freedom. This is the case for La_{2-x}Sr_{x}NiO_{4+δ}, in which coupled incommensurate charge and spin stripes form at low temperatures. Here, we use resonant x-ray photon correlation spectroscopy to study the temporal stability and domain memory of the charge and spin stripes in La_{2-x}Sr_{x}NiO_{4+δ}. Although spin stripes are more spatially correlated, charge stripes maintain a better temporal stability against temperature change. More intriguingly, charge order shows robust domain memory with thermal cycling up to 250 K, far above the ordering temperature. These results demonstrate the pinning of charge stripes to the lattice and that charge condensation is the predominant factor in the formation of stripe orders in nickelates.
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Affiliation(s)
- Y Shen
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - G Fabbris
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
- Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - H Miao
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
- Material Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - Y Cao
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - D Meyers
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA
| | - D G Mazzone
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - T A Assefa
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - X M Chen
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - K Kisslinger
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - D Prabhakaran
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford OX1 3PU, United Kingdom
| | - A T Boothroyd
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford OX1 3PU, United Kingdom
| | - J M Tranquada
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - W Hu
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - A M Barbour
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - S B Wilkins
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - C Mazzoli
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - I K Robinson
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - M P M Dean
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
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32
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Fermi surface in La-based cuprate superconductors from Compton scattering imaging. Nat Commun 2021; 12:2223. [PMID: 33850119 PMCID: PMC8044246 DOI: 10.1038/s41467-021-22229-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 03/01/2021] [Indexed: 11/09/2022] Open
Abstract
Compton scattering provides invaluable information on the underlying Fermi surface (FS) and is a powerful tool complementary to angle-resolved photoemission spectroscopy and quantum oscillation measurements. Here we perform high-resolution Compton scattering measurements for La2−xSrxCuO4 with x = 0.08 (Tc = 20 K) at 300 K and 150 K, and image the momentum distribution function in the two-dimensional Brillouin zone. We find that the observed images cannot be reconciled with the conventional hole-like FS believed so far. Instead, our data imply that the FS is strongly deformed by the underlying nematicity in each CuO2 plane, but the bulk FSs recover the fourfold symmetry. We also find an unusually strong temperature dependence of the momentum distribution function, which may originate from the pseudogap formation in the presence of the reconstructed FSs due to the underlying nematicity. Additional measurements for x = 0.15 and 0.30 at 300 K suggest similar FS deformation with weaker nematicity, which nearly vanishes at x = 0.30. Compton scattering provides information on the Fermi surface (FS) hence very useful to understand the electronic structure of high temperature superconductors. Here, Yamase et al. perform Compton scattering measurements on La2−xSrxCuO4 samples and observe deformed FS in CuO2 plane due to nematicity but recovering fourfold symmetry in bulk FS.
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33
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Incommensurate smectic phase in close proximity to the high-T c superconductor FeSe/SrTiO 3. Nat Commun 2021; 12:2196. [PMID: 33850158 PMCID: PMC8044195 DOI: 10.1038/s41467-021-22516-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 03/18/2021] [Indexed: 11/23/2022] Open
Abstract
Superconductivity is significantly enhanced in monolayer FeSe grown on SrTiO3, but not for multilayer films, in which large strength of nematicity develops. However, the link between the high-transition temperature superconductivity in monolayer and the correlation related nematicity in multilayer FeSe films is not well understood. Here, we use low-temperature scanning tunneling microscopy to study few-layer FeSe thin films grown by molecular beam epitaxy. We observe an incommensurate long-range smectic phase, which solely appears in bilayer FeSe films. The smectic order still locally exists and gradually fades away with increasing film thickness, while it suddenly vanishes in monolayer FeSe, indicative of an abrupt smectic phase transition. Surface alkali-metal doping can suppress the smectic phase and induce high-Tc superconductivity in bilayer FeSe. Our observations provide evidence that the monolayer FeSe is in close proximity to the smectic phase, and its superconductivity is likely enhanced by this electronic instability as well. The relation between enhanced superconductivity in monolayer FeSe grown on SrTiO3 and the large nematicity in multilayer FeSe on SrTiO3 remains not well understood. Here, the authors observe a long-range smectic phase in bilayer FeSe films but vanishes in monolayer FeSe, providing a new instability to help enhance the superconductivity.
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34
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Dynamic electron correlations with charge order wavelength along all directions in the copper oxide plane. Nat Commun 2021; 12:597. [PMID: 33500415 PMCID: PMC7838423 DOI: 10.1038/s41467-020-20824-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/21/2020] [Indexed: 11/08/2022] Open
Abstract
In strongly correlated systems the strength of Coulomb interactions between electrons, relative to their kinetic energy, plays a central role in determining their emergent quantum mechanical phases. We perform resonant x-ray scattering on Bi2Sr2CaCu2O8+δ, a prototypical cuprate superconductor, to probe electronic correlations within the CuO2 plane. We discover a dynamic quasi-circular pattern in the x-y scattering plane with a radius that matches the wave vector magnitude of the well-known static charge order. Along with doping- and temperature-dependent measurements, our experiments reveal a picture of charge order competing with superconductivity where short-range domains along x and y can dynamically rotate into any other in-plane direction. This quasi-circular spectrum, a hallmark of Brazovskii-type fluctuations, has immediate consequences to our understanding of rotational and translational symmetry breaking in the cuprates. We discuss how the combination of short- and long-range Coulomb interactions results in an effective non-monotonic potential that may determine the quasi-circular pattern. Knowledge of effective Coulomb interactions is central to understand emergent quantum phases in strongly correlated systems. Here, Boschini et al. report a dynamic quasi-circular spectrum of charge density wave fluctuations in the CuO2 plane of Bi2Sr2CaCu2O8+δ, shedding a light on understanding how Coulomb interactions can lead to rotational and translational symmetry breaking in the cuprates.
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35
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Radzihovsky L. Quantum Smectic Gauge Theory. PHYSICAL REVIEW LETTERS 2020; 125:267601. [PMID: 33449738 DOI: 10.1103/physrevlett.125.267601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 11/04/2020] [Indexed: 06/12/2023]
Abstract
We present a gauge theory formulation of a two-dimensional quantum smectic and its relatives, motivated by their realizations in correlated quantum matter. The description gives a unified treatment of phonons and topological defects, respectively, encoded in a pair of coupled gauge fields and corresponding charges. The charges exhibit subdimensional constrained quantum dynamics and anomalously slow highly anisotropic diffusion of disclinations inside a smectic. This approach gives a transparent description of a multistage quantum melting transition of a two-dimensional commensurate crystal (through an incommensurate crystal-a supersolid) into a quantum smectic, which subsequently melts into a quantum nematic and isotropic superfluids, all in terms of a sequence of Higgs transitions.
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Affiliation(s)
- Leo Radzihovsky
- Department of Physics and Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA
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36
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Saraiva TT, Cavalcanti PJF, Vagov A, Vasenko AS, Perali A, Dell'Anna L, Shanenko AA. Multiband Material with a Quasi-1D Band as a Robust High-Temperature Superconductor. PHYSICAL REVIEW LETTERS 2020; 125:217003. [PMID: 33275004 DOI: 10.1103/physrevlett.125.217003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/26/2020] [Accepted: 10/26/2020] [Indexed: 06/12/2023]
Abstract
It is well known that superconductivity in quasi-one-dimensional (Q1D) materials is hindered by large fluctuations of the order parameter. They reduce the critical temperature and can even destroy the superconductivity altogether. Here it is demonstrated that the situation changes dramatically when a Q1D pair condensate is coupled to a higher-dimensional stable one, as in recently discovered multiband Q1D superconductors. The fluctuations are suppressed even by vanishingly small pair-exchange coupling between different band condensates and the superconductor is well described by the mean field theory. In this case the low dimensionality effects enhance the coherence of the system instead of suppressing it. As a result, the critical temperature of the multiband Q1D superconductor can increase by orders of magnitude when the system is tuned to the Lifshitz transition with the Fermi level close to the edge of the Q1D band.
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Affiliation(s)
- T T Saraiva
- National Research University Higher School of Economics, 101000 Moscow, Russia
| | - P J F Cavalcanti
- Departamento de Fsica, Universidade Federal de Pernambuco, Cidade Universitria, 50670-901 Recife-PE, Brazil
| | - A Vagov
- Institut für Theoretische Physik III, Bayreuth Universität, Bayreuth 95440, Germany
| | - A S Vasenko
- National Research University Higher School of Economics, 101000 Moscow, Russia
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, San Sebastián/Donostia, 20018 Basque Country, Spain
| | - A Perali
- School of Pharmacy, Physics Unit, University of Camerino, I-62032 Camerino, Italy
| | - L Dell'Anna
- Dipartimento di Fisica e Astronomia "Galileo Galilei," Università di Padova, Via Marzolo 8, 35131 Padova, Italy
| | - A A Shanenko
- National Research University Higher School of Economics, 101000 Moscow, Russia
- Departamento de Fisica, Universidade Federal de Pernambuco, Cidade Universitaria, 50670-901 Recife-PE, Brazil
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37
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Le T, Sun Y, Jin HK, Che L, Yin L, Li J, Pang G, Xu C, Zhao L, Kittaka S, Sakakibara T, Machida K, Sankar R, Yuan H, Chen G, Xu X, Li S, Zhou Y, Lu X. Evidence for nematic superconductivity of topological surface states in PbTaSe 2. Sci Bull (Beijing) 2020; 65:1349-1355. [PMID: 36659213 DOI: 10.1016/j.scib.2020.04.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/27/2020] [Accepted: 04/23/2020] [Indexed: 01/21/2023]
Abstract
Spontaneous symmetry breaking has been a paradigm to describe the phase transitions in condensed matter physics. In addition to the continuous electromagnetic gauge symmetry, an unconventional superconductor can break discrete symmetries simultaneously, such as time reversal and lattice rotational symmetry. In this work we report a characteristic in-plane 2-fold behaviour of the resistive upper critical field and point-contact spectra on the superconducting semimetal PbTaSe2 with topological nodal-rings, despite its hexagonal lattice symmetry (or D3h in bulk while C3v on surface, to be precise). The 2-fold behaviour persists up to its surface upper critical field Hc2R even though bulk superconductivity has been suppressed at its bulk upper critical field Hc2HC≪Hc2R, signaling its probable surface-only electronic nematicity. In addition, we do not observe any lattice rotational symmetry breaking signal from field-angle-dependent specific heat within the resolution. It is worth noting that such surface-only electronic nematicity is in sharp contrast to the observation in the topological superconductor candidate, CuxBi2Se3, where the nematicity occurs in various bulk measurements. In combination with theory, superconducting nematicity is likely to emerge from the topological surface states of PbTaSe2, rather than the proximity effect. The issue of time reversal symmetry breaking is also addressed. Thus, our results on PbTaSe2 shed new light on possible routes to realize nematic superconductivity with nontrivial topology.
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Affiliation(s)
- Tian Le
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
| | - Yue Sun
- Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara 252-5258, Japan.
| | - Hui-Ke Jin
- Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Liqiang Che
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
| | - Lichang Yin
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
| | - Jie Li
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
| | - Guiming Pang
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China
| | - Chunqiang Xu
- Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China
| | - Lingxiao Zhao
- Beijing National Laboratory for Condensed Matter Physics & Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Shunichiro Kittaka
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Toshiro Sakakibara
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Kazushige Machida
- Department of Physics, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
| | - Raman Sankar
- Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan, China
| | - Huiqiu Yuan
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Genfu Chen
- Beijing National Laboratory for Condensed Matter Physics & Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Xiaofeng Xu
- Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China.
| | - Shiyan Li
- State Key Laboratory of Surface Physics, Department of Physics, and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Yi Zhou
- Beijing National Laboratory for Condensed Matter Physics & Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100190, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China; Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Xin Lu
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
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38
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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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39
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Kostylev I, Yonezawa S, Wang Z, Ando Y, Maeno Y. Uniaxial-strain control of nematic superconductivity in Sr xBi 2Se 3. Nat Commun 2020; 11:4152. [PMID: 32839435 PMCID: PMC7445267 DOI: 10.1038/s41467-020-17913-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 07/24/2020] [Indexed: 12/02/2022] Open
Abstract
Nematic states are characterized by rotational symmetry breaking without translational ordering. Recently, nematic superconductivity, in which the superconducting gap spontaneously lifts the rotational symmetry of the lattice, has been discovered. In nematic superconductivity, multiple superconducting domains with different nematic orientations can exist, and these domains can be controlled by a conjugate external stimulus. Domain engineering is quite common in magnets but has not been achieved in superconductors. Here, we report control of the nematic superconductivity and their domains of SrxBi2Se3, through externally-applied uniaxial stress. The suppression of subdomains indicates that it is the Δ4y state that is most favoured under compression along the basal Bi-Bi bonds. This fact allows us to determine the coupling parameter between the nematicity and lattice distortion. These results provide an inevitable step towards microscopic understanding and future utilization of the unique topological nematic superconductivity.
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Affiliation(s)
- Ivan Kostylev
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan.
| | - Shingo Yonezawa
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan.
| | - Zhiwei Wang
- Institute of Physics II, University of Cologne, Köln, 50937, Germany
- Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement, Ministry of Education (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Yoichi Ando
- Institute of Physics II, University of Cologne, Köln, 50937, Germany
| | - Yoshiteru Maeno
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
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40
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Hong X, Caglieris F, Kappenberger R, Wurmehl S, Aswartham S, Scaravaggi F, Lepucki P, Wolter AUB, Grafe HJ, Büchner B, Hess C. Evolution of the Nematic Susceptibility in LaFe_{1-x}Co_{x}AsO. PHYSICAL REVIEW LETTERS 2020; 125:067001. [PMID: 32845654 DOI: 10.1103/physrevlett.125.067001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Revised: 06/26/2020] [Accepted: 07/07/2020] [Indexed: 06/11/2023]
Abstract
We report a systematic elastoresistivity study on LaFe_{1-x}Co_{x}AsO single crystals, which have well separated structural and magnetic transition lines. All crystals show a Curie-Weiss-like nematic susceptibility in the tetragonal phase. The extracted nematic temperature is monotonically suppressed upon cobalt doping, and changes sign around the optimal doping level, indicating a possible nematic quantum critical point beneath the superconducting dome. The amplitude of the nematic susceptibility shows a peculiar double-peak feature. This could be explained by a combined effect of different contributions to the nematic susceptibility, which are amplified at separated doping levels of LaFe_{1-x}Co_{x}AsO.
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Affiliation(s)
- Xiaochen Hong
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Federico Caglieris
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Rhea Kappenberger
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Sabine Wurmehl
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Saicharan Aswartham
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Francesco Scaravaggi
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
- Institute of Solid State and Materials Physics, Technische Universität Dresden, 01069 Dresden, Germany
| | - Piotr Lepucki
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Anja U B Wolter
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Hans-Joachim Grafe
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
| | - Bernd Büchner
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
- Institute of Solid State and Materials Physics, Technische Universität Dresden, 01069 Dresden, Germany
- Center for Transport and Devices, Technische Universität Dresden, 01069 Dresden, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062 Dresden, Germany
| | - Christian Hess
- Leibniz-Institute for Solid State and Materials Research (IFW Dresden), 01069 Dresden, Germany
- Center for Transport and Devices, Technische Universität Dresden, 01069 Dresden, Germany
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41
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Chan MK, McDonald RD, Ramshaw BJ, Betts JB, Shekhter A, Bauer ED, Harrison N. Extent of Fermi-surface reconstruction in the high-temperature superconductor HgBa 2CuO 4+δ. Proc Natl Acad Sci U S A 2020; 117:9782-9786. [PMID: 32317380 PMCID: PMC7211972 DOI: 10.1073/pnas.1914166117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
High magnetic fields have revealed a surprisingly small Fermi surface in underdoped cuprates, possibly resulting from Fermi-surface reconstruction due to an order parameter that breaks translational symmetry of the crystal lattice. A crucial issue concerns the doping extent of such a state and its relationship to the principal pseudogap and superconducting phases. We employ pulsed magnetic-field measurements on the cuprate [Formula: see text]Cu[Formula: see text] to identify signatures of Fermi-surface reconstruction from a sign change of the Hall effect and a peak in the temperature-dependent planar resistivity. We trace the termination of Fermi-surface reconstruction to two hole concentrations where the superconducting upper critical fields are found to be enhanced. One of these points is associated with the pseudogap endpoint near optimal doping. These results connect the Fermi-surface reconstruction to both superconductivity and the pseudogap phenomena.
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Affiliation(s)
- Mun K Chan
- Pulsed Field Facility, National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545;
| | - Ross D McDonald
- Pulsed Field Facility, National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - B J Ramshaw
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853
| | - Jon B Betts
- Pulsed Field Facility, National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Arkady Shekhter
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310
| | - Eric D Bauer
- Materials Physics and Applications-QUANTUM, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Neil Harrison
- Pulsed Field Facility, National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545
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42
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Abstract
We have measured the angle-resolved transverse resistivity (ARTR), a sensitive indicator of electronic anisotropy, in high-quality thin films of the unconventional superconductor Sr2RuO4 grown on various substrates. The ARTR signal, heralding the electronic nematicity or a large nematic susceptibility, is present and substantial already at room temperature and grows by an order of magnitude upon cooling down to 4 K. In Sr2RuO4 films deposited on tetragonal substrates the highest-conductivity direction does not coincide with any crystallographic axis. In films deposited on orthorhombic substrates it tends to align with the shorter axis; however, the magnitude of the anisotropy stays the same despite the large lattice distortion. These are strong indications of actual or incipient electronic nematicity in Sr2RuO4.
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43
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Lee JM, Geng C, Park JW, Oshikawa M, Lee SS, Yeom HW, Cho GY. Stable Flatbands, Topology, and Superconductivity of Magic Honeycomb Networks. PHYSICAL REVIEW LETTERS 2020; 124:137002. [PMID: 32302191 DOI: 10.1103/physrevlett.124.137002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Revised: 11/08/2019] [Accepted: 03/06/2020] [Indexed: 06/11/2023]
Abstract
We propose a new principle to realize flatbands which are robust in real materials, based on a network superstructure of one-dimensional segments. This mechanism is naturally realized in the nearly commensurate charge-density wave of 1T-TaS_{2} with the honeycomb network of conducting domain walls, and the resulting flatband can naturally explain the enhanced superconductivity. We also show that corner states, which are a hallmark of the higher-order topological insulators, appear in the network superstructure.
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Affiliation(s)
- Jongjun M Lee
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Chenhua Geng
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Jae Whan Park
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Korea
| | - Masaki Oshikawa
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Sung-Sik Lee
- Department of Physics & Astronomy, McMaster University, 1280 Main St. W., Hamilton Ontario L85 4M1, Canada
- Perimeter Institute for Theoretical Physics, 31 Caroline ST. N., Waterloo Ontario N2L 2Y5, Canada
| | - Han Woong Yeom
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Korea
| | - Gil Young Cho
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
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44
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Murthy C, Nayak C. Almost Perfect Metals in One Dimension. PHYSICAL REVIEW LETTERS 2020; 124:136801. [PMID: 32302200 DOI: 10.1103/physrevlett.124.136801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/25/2020] [Indexed: 06/11/2023]
Abstract
We show that a one-dimensional quantum wire with as few as two channels of interacting fermions can host metallic states of matter that are stable against all perturbations up to qth order in fermion creation or annihilation operators for any fixed finite q. Thus, the leading relevant perturbations are complicated operators that are expected to modify the physics only at very low energies, below accessible temperatures. The stability of these non-Fermi liquid fixed points is due to strong interactions between the channels, which can (but need not) be chosen to be purely repulsive. Our results might enable elementary physical realizations of these phases.
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Affiliation(s)
- Chaitanya Murthy
- Department of Physics, University of California, Santa Barbara, California 93106, USA
| | - Chetan Nayak
- Department of Physics, University of California, Santa Barbara, California 93106, USA
- Microsoft Quantum, Station Q, University of California, Santa Barbara, California 93106, USA
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45
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Novel electronic nematicity in heavily hole-doped iron pnictide superconductors. Proc Natl Acad Sci U S A 2020; 117:6424-6429. [PMID: 32165540 DOI: 10.1073/pnas.1909172117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Electronic nematicity, a correlated state that spontaneously breaks rotational symmetry, is observed in several layered quantum materials. In contrast to their liquid-crystal counterparts, the nematic director cannot usually point in an arbitrary direction (XY nematics), but is locked by the crystal to discrete directions (Ising nematics), resulting in strongly anisotropic fluctuations above the transition. Here, we report on the observation of nearly isotropic XY-nematic fluctuations, via elastoresistance measurements, in hole-doped Ba1-x Rb x Fe2As2 iron-based superconductors. While for [Formula: see text], the nematic director points along the in-plane diagonals of the tetragonal lattice, for [Formula: see text], it points along the horizontal and vertical axes. Remarkably, for intermediate doping, the susceptibilities of these two symmetry-irreducible nematic channels display comparable Curie-Weiss behavior, thus revealing a nearly XY-nematic state. This opens a route to assess this elusive electronic quantum liquid-crystalline state.
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46
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Gati E, Xiang L, Bud'ko SL, Canfield PC. Measurements of elastoresistance under pressure by combining in-situ tunable quasi-uniaxial stress with hydrostatic pressure. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:023904. [PMID: 32113408 DOI: 10.1063/1.5139437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
Uniaxial stress, as well as hydrostatic pressure are often used to tune material properties in condensed matter physics. Here, we present a setup that allows for the study of the combined effects of quasi-uniaxial stress and hydrostatic pressure. Following earlier designs for measurements under finite stress at ambient pressures [e.g., Chu et al., Science 337, 710 (2012)], the present setup utilizes a piezoelectric actuator to change stress in situ inside the piston-cylinder pressure cell. We show that the actuator can be operated over the full temperature (from 30 K up to 260 K) and pressure range (up to ≈2 GPa), resulting in a clear and measurable quasi-uniaxial strain. To demonstrate functionality, measurements of the elastoresistance (i.e., the change of resistance of a sample as a response to quasi-uniaxial strain) under finite hydrostatic pressure on the iron-based compound BaFe2As2 are presented as a proof-of-principle example and discussed in the framework of electronic nematicity. Overall, this work introduces the combination of in situ tunable quasi-uniaxial stress and large (up to ≈2 GPa) hydrostatic pressure as a powerful combination in the study of novel electronic phases. In addition, it also points toward further technical advancements which can be made in the future.
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Affiliation(s)
- Elena Gati
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
| | - Li Xiang
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
| | - Sergey L Bud'ko
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
| | - Paul C Canfield
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
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47
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Miao L, Peng Y, Wang D, Liang J, Hu C, Nishibori E, Sun L, Fisher CAJ, Tanemura S. Characterisation of the temperature-dependent M1 to R phase transition in W-doped VO2 nanorod aggregates by Rietveld refinement and theoretical modelling. Phys Chem Chem Phys 2020; 22:7984-7994. [DOI: 10.1039/d0cp01058h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Synchrotron XRD Rietveld refinement is combined with first-principles calculations to probe the effect of W doping on the IMT mechanism in VO2 nanorods, providing insights into the connection between atomic-scale phenomena and macro-scale properties.
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Affiliation(s)
- Lei Miao
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
| | - Ying Peng
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
| | - Dianhui Wang
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
| | - Jihui Liang
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
| | - Chaohao Hu
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
| | - Eiji Nishibori
- Division of Physics
- Faculty of Pure and Applied Sciences
- Tsukuba Research Center for Energy Materials Science (TREMS)
- University of Tsukuba
- Tsukuba
| | - Lixian Sun
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
| | | | - Sakae Tanemura
- Guangxi Key Laboratory of Information Material
- Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials
- School of Materials Science and Engineering
- Guilin University of Electronic Technology
- Guilin
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48
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Eckberg C, Campbell DJ, Metz T, Collini J, Hodovanets H, Drye T, Zavalij P, Christensen MH, Fernandes RM, Lee S, Abbamonte P, Lynn JW, Paglione J. Sixfold enhancement of superconductivity in a tunable electronic nematic system. NATURE PHYSICS 2020; 16:346-350. [PMID: 33505513 PMCID: PMC7836097 DOI: 10.1038/s41567-019-0736-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 11/05/2019] [Indexed: 06/11/2023]
Abstract
The electronic nematic phase-in which electronic degrees of freedom lower the crystal rotational symmetry-is commonly observed in high-temperature superconductors. However, understanding the role of nematicity and nematic fluctuations in Cooper pairing is often made more complicated by the coexistence of other orders, particularly long-range magnetic order. Here we report the enhancement of superconductivity in a model electronic nematic system that is not magnetic, and show that the enhancement is directly born out of strong nematic fluctuations associated with a quantum phase transition. We present measurements of the resistance as a function of strain in Ba1-x Sr x Ni2As2 to show that strontium substitution promotes an electronically driven nematic order in this system. In addition, the complete suppression of that order to absolute zero temperature leads to an enhancement of the pairing strength, as evidenced by a sixfold increase in the superconducting transition temperature. The direct relation between enhanced pairing and nematic fluctuations in this model system, as well as the interplay with a unidirectional charge-density-wave order comparable to that found in the cuprates, offers a means to investigate the role of nematicity in strengthening superconductivity.
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Affiliation(s)
- Chris Eckberg
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Daniel J. Campbell
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Tristin Metz
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - John Collini
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Halyna Hodovanets
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Tyler Drye
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
| | - Peter Zavalij
- Department of Chemistry, University of Maryland, College Park, MD, USA
| | | | - Rafael M. Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA
| | - Sangjun Lee
- Department of Physics, Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Peter Abbamonte
- Department of Physics, Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jeffrey W. Lynn
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Johnpierre Paglione
- Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA
- The Canadian Institute for Advanced Research, Toronto, Ontario, Canada
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49
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Wang X, Yuan Y, Xue QK, Li W. Charge ordering in high-temperature superconductors visualized by scanning tunneling microscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:013002. [PMID: 31487703 DOI: 10.1088/1361-648x/ab41c5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Since the discovery of stripe order in La1.6-x Nd0.4Sr x CuO4 superconductors in 1995, charge ordering in cuprate superconductors has been intensively studied by various experimental techniques. Among these studies, scanning tunneling microscope (STM) plays an irreplaceable role in determining the real space structures of charge ordering. STM imaging of different families of cuprates over a wide range of doping levels reveal similar checkerboard-like patterns, indicating that such a charge ordered state is likely a ubiquitous and intrinsic characteristic of cuprate superconductors, which may shed light on understanding the mechanism of high-temperature superconductivity. In another class of high-temperature superconductors, iron-based superconductors, STM studies reveal several charge ordered states as well, but their real-space patterns and the interplay with superconductivity are markedly different among different materials. In this paper, we present a brief review on STM studies of charge ordering in these two classes of high-temperature superconductors. Possible origins of charge ordering and its interplay with superconductivity will be discussed.
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Affiliation(s)
- Xintong Wang
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China. Collaborative Innovation Center of Quantum Matter, Beijing 100084, People's Republic of China
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50
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Reber TJ, Zhou X, Plumb NC, Parham S, Waugh JA, Cao Y, Sun Z, Li H, Wang Q, Wen JS, Xu ZJ, Gu G, Yoshida Y, Eisaki H, Arnold GB, Dessau DS. A unified form of low-energy nodal electronic interactions in hole-doped cuprate superconductors. Nat Commun 2019; 10:5737. [PMID: 31844065 PMCID: PMC6914777 DOI: 10.1038/s41467-019-13497-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 11/08/2019] [Indexed: 11/13/2022] Open
Abstract
Using angle resolved photoemission spectroscopy measurements of Bi2Sr2CaCu2O8+δ over a wide range of doping levels, we present a universal form for the non-Fermi liquid electronic interactions in the nodal direction in the exotic normal state phase. It is described by a continuously varying power law exponent versus energy and temperature (hence named a Power Law Liquid or PLL), which with doping varies smoothly from a quadratic Fermi Liquid in the overdoped regime, to a linear Marginal Fermi Liquid at optimal doping, to a non-quasiparticle non-Fermi Liquid in the underdoped regime. The coupling strength is essentially constant across all regimes and is consistent with Planckian dissipation. Using the extracted PLL parameters we reproduce the experimental optics and resistivity over a wide range of doping and normal-state temperature values, including the T* pseudogap temperature scale observed in the resistivity curves. This breaks the direct link to the pseudogapping of antinodal spectral weight observed at similar temperature scales and gives an alternative direction for searches of the microscopic mechanism. The normal state of hole-doped, high-temperature superconductors is a currently-unexplained "strange metal" with exotic electronic behaviour. Here, the authors show that a doping-dependent power law ansatz for the electronic scattering phenomenologically captures ARPES, transport and optics observations.
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Affiliation(s)
- T J Reber
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA. .,Department of Chemistry, University of Georgia, Athens, GA, 30602, USA.
| | - X Zhou
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA.
| | - N C Plumb
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA.,Swiss Light Source, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - S Parham
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - J A Waugh
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - Y Cao
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - Z Sun
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA.,University of Science and Technology of China, Hefei, China
| | - H Li
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - Q Wang
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - J S Wen
- Condensed Matter Physics and Materials Science Department, Brookhaven National Labs, Upton, NY, 11973, USA
| | - Z J Xu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Labs, Upton, NY, 11973, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Labs, Upton, NY, 11973, USA
| | - Y Yoshida
- AIST Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki, 3058568, Japan
| | - H Eisaki
- AIST Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki, 3058568, Japan
| | - G B Arnold
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - D S Dessau
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA. .,Center for Experiments on Quantum Materials, University of Colorado, Boulder, CO, 80309-0390, USA.
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