1
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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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2
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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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3
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Watanabe H, Shirakawa T, Seki K, Sakakibara H, Kotani T, Ikeda H, Yunoki S. Monte Carlo study of cuprate superconductors in a four-bandd-pmodel: role of orbital degrees of freedom. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:195601. [PMID: 36866651 DOI: 10.1088/1361-648x/acc0bf] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
Understanding the various competing phases in cuprate superconductors is a long-standing challenging problem. Recent studies have shown that orbital degrees of freedom, both Cuegorbitals and Oporbitals, are a key ingredient for a unified understanding of cuprate superconductors, including the material dependence. Here we investigate a four-bandd-pmodel derived from the first-principles calculations with the variational Monte Carlo method, which allows us to elucidate competing phases on an equal footing. The obtained results can consistently explain the doping dependence of superconductivity, antiferromagnetic and stripe phases, phase separation in the underdoped region, and also novel magnetism in the heavily-overdoped region. The presence ofporbitals is critical to the charge-stripe features, which induce two types of stripe phases withs)-wave andd-wave bond stripe. On the other hand, the presence ofdz2orbital is indispensable to material dependence of the superconducting transition temperature (Tc), and enhances local magnetic moment as a source of novel magnetism in the heavily-overdoped region as well. These findings beyond one-band description could provide a major step toward a full explanation of unconventional normal state and highTcin cuprate supercondutors.
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Affiliation(s)
- Hiroshi Watanabe
- Research Organization of Science and Technology, Ritsumeikan University, Shiga 525-8577, Japan
| | - Tomonori Shirakawa
- Computational Materials Science Research Team, RIKEN Center for Computational Science (R-CCS), Hyogo 650-0047, Japan
- Quantum Computational Science Research Team, RIKEN Center for Quantum Computing (RQC), Saitama 351-0198, Japan
| | - Kazuhiro Seki
- Quantum Computational Science Research Team, RIKEN Center for Quantum Computing (RQC), Saitama 351-0198, Japan
| | - Hirofumi Sakakibara
- Advanced Mechanical and Electronic System Research Center (AMES), Faculty of Engineering, Tottori University, Tottori 680-8552, Japan
- Center of Spintronics Research Network (CSRN), Graduate School of Engineering Science, Osaka University, Osaka 560-8531, Japan
- Computational Condensed Matter Physics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama 351-0198, Japan
| | - Takao Kotani
- Advanced Mechanical and Electronic System Research Center (AMES), Faculty of Engineering, Tottori University, Tottori 680-8552, Japan
- Center of Spintronics Research Network (CSRN), Graduate School of Engineering Science, Osaka University, Osaka 560-8531, Japan
| | - Hiroaki Ikeda
- Department of Physics, Ritsumeikan University, Shiga 525-8577, Japan
| | - Seiji Yunoki
- Computational Materials Science Research Team, RIKEN Center for Computational Science (R-CCS), Hyogo 650-0047, Japan
- Quantum Computational Science Research Team, RIKEN Center for Quantum Computing (RQC), Saitama 351-0198, Japan
- Computational Condensed Matter Physics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama 351-0198, Japan
- Computational Quantum Matter Research Team, RIKEN Center for Emergent Matter Science (CEMS), Saitama 351-0198, Japan
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4
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Pandey S, Zhang H, Yang J, May AF, Sanchez JJ, Liu Z, Chu JH, Kim JW, Ryan PJ, Zhou H, Liu J. Controllable Emergent Spatial Spin Modulation in Sr_{2}IrO_{4} by In Situ Shear Strain. PHYSICAL REVIEW LETTERS 2022; 129:027203. [PMID: 35867461 DOI: 10.1103/physrevlett.129.027203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Symmetric anisotropic interaction can be ferromagnetic and antiferromagnetic at the same time but for different crystallographic axes. We show that the competition of anisotropic interactions of orthogonal irreducible representations can be a general route to obtain new exotic magnetic states. We demonstrate it here by observing the emergence of a continuously tunable 12-layer spatial spin modulation when distorting the square-lattice planes in the quasi-two-dimensional antiferromagnetic Sr_{2}IrO_{4} under in situ shear strain. This translation-symmetry-breaking phase is a result of an unusual strain-activated anisotropic interaction which is at the fourth order and competing with the inherent quadratic anisotropic interaction. Such a mechanism of competing anisotropy is distinct from that among the ferromagnetic, antiferromagnetic, and/or the Dzyaloshinskii-Moriya interactions, and it could be widely applicable and highly controllable in low-dimensional magnets.
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Affiliation(s)
- Shashi Pandey
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Han Zhang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Junyi Yang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Andrew F May
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Joshua J Sanchez
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Zhaoyu Liu
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Jiun-Haw Chu
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Jong-Woo Kim
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Philip J Ryan
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
- School of Physical Sciences, Dublin City University, Dublin 11, Ireland
| | - Haidong Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Jian Liu
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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5
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Barišić N, Sunko DK. High-T c Cuprates: a Story of Two Electronic Subsystems. JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM 2022; 35:1781-1799. [PMID: 35756097 PMCID: PMC9217785 DOI: 10.1007/s10948-022-06183-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/12/2022] [Indexed: 06/15/2023]
Abstract
A review of the phenomenology and microscopy of cuprate superconductors is presented, with particular attention to universal conductance features, which reveal the existence of two electronic subsystems. The overall electronic system consists of 1 + p charges, where p is the doping. At low dopings, exactly one hole is localized per planar copper-oxygen unit, while upon increasing doping and temperature, the hole is gradually delocalized and becomes itinerant. Remarkably, the itinerant holes exhibit identical Fermi liquid character across the cuprate phase diagram. This universality enables a simple count of carrier density and yields comprehensive understanding of the key features in the normal and superconducting state. A possible superconducting mechanism is presented, compatible with the key experimental facts. The base of this mechanism is the interaction of fast Fermi liquid carriers with localized holes. A change in the microscopic nature of chemical bonding in the copper oxide planes, from ionic to covalent, is invoked to explain the phase diagram of these fascinating compounds.
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Affiliation(s)
- N. Barišić
- Department of Physics, Faculty of Science, University of Zagreb, Zagreb, 10000 Croatia
- Institute of Solid State Physics, TU Wien, Vienna, 1040 Austria
| | - D. K. Sunko
- Department of Physics, Faculty of Science, University of Zagreb, Zagreb, 10000 Croatia
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6
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Oh D, Song D, Kim Y, Miyasaka S, Tajima S, Bok JM, Bang Y, Park SR, Kim C. B_{1g}-Phonon Anomaly Driven by Fermi Surface Instability at Intermediate Temperature in YBa_{2}Cu_{3}O_{7-δ}. PHYSICAL REVIEW LETTERS 2021; 127:277001. [PMID: 35061420 DOI: 10.1103/physrevlett.127.277001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/14/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
We performed temperature- and doping-dependent high-resolution Raman spectroscopy experiments on YBa_{2}Cu_{3}O_{7-δ} to study B_{1g} phonons. The temperature dependence of the real part of the phonon self-energy shows a distinct kink at T=T_{B1g} above T_{c} due to softening, in addition to the one due to the onset of the superconductivity. T_{B1g} is clearly different from the pseudogap temperature with a maximum in the underdoped region and resembles charge density wave onset temperature, T_{CDW}. We attribute the B_{1g}-phonon softening to an energy gap on the Fermi surface induced by a charge density wave order, which is consistent with the results of a recent electronic Raman scattering study. Our work demonstrates a way to investigate Fermi surface instabilities above T_{c} via phonon Raman studies.
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Affiliation(s)
- Dongjin Oh
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Dongjoon Song
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Younsik Kim
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | | | - Setsuko Tajima
- Department of Physics, Osaka University, Osaka 560-0043, Japan
| | - Jin Mo Bok
- Department of Physics, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
- Asia Pacific Center for Theoretical Physics, Pohang 37673, Korea
| | - Yunkyu Bang
- Department of Physics, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
- Asia Pacific Center for Theoretical Physics, Pohang 37673, Korea
| | - Seung Ryong Park
- Department of Physics, Incheon National University, Incheon 22012, Republic of Korea
- Intelligent Sensor Convergence Research Center (ISCRC), Incheon National University, Incheon 22012, Republic of Korea
| | - Changyoung Kim
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
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7
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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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8
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El Baggari I, Baek DJ, Zachman MJ, Lu D, Hikita Y, Hwang HY, Nowadnick EA, Kourkoutis LF. Charge order textures induced by non-linear couplings in a half-doped manganite. Nat Commun 2021; 12:3747. [PMID: 34145244 PMCID: PMC8213702 DOI: 10.1038/s41467-021-24026-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 05/28/2021] [Indexed: 11/13/2022] Open
Abstract
The self-organization of strongly interacting electrons into superlattice structures underlies the properties of many quantum materials. How these electrons arrange within the superlattice dictates what symmetries are broken and what ground states are stabilized. Here we show that cryogenic scanning transmission electron microscopy (cryo-STEM) enables direct mapping of local symmetries and order at the intra-unit-cell level in the model charge-ordered system Nd1/2Sr1/2MnO3. In addition to imaging the prototypical site-centered charge order, we discover the nanoscale coexistence of an exotic intermediate state which mixes site and bond order and breaks inversion symmetry. We further show that nonlinear coupling of distinct lattice modes controls the selection between competing ground states. The results demonstrate the importance of lattice coupling for understanding and manipulating the character of electronic self-organization and that cryo-STEM can reveal local order in strongly correlated systems at the atomic scale. In this paper, the authors demonstrate that cryogenic scanning transmission electron microscopy allows for the direct mapping of the local arrangements and symmetries of electronic order, providing a useful method for studying strongly correlated systems. They show this using the example of Nd1/2Sr1/2MnO3, a model charge ordered material.
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Affiliation(s)
| | - David J Baek
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA.,Intel Corp., Hillsboro, OR, USA
| | - Michael J Zachman
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.,Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Di Lu
- Department of Physics, Stanford University, Stanford, CA, USA.,Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Materials Science and Engineering, Northwestern University, Evanston, IL, USA
| | - Yasuyuki Hikita
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Harold Y Hwang
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Elizabeth A Nowadnick
- Department of Materials Science and Engineering, University of California Merced, Merced, CA, USA
| | - Lena F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA. .,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA.
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9
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Vinograd I, Zhou R, Hirata M, Wu T, Mayaffre H, Krämer S, Liang R, Hardy WN, Bonn DA, Julien MH. Locally commensurate charge-density wave with three-unit-cell periodicity in YBa 2Cu 3O y. Nat Commun 2021; 12:3274. [PMID: 34075033 PMCID: PMC8169916 DOI: 10.1038/s41467-021-23140-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/16/2021] [Indexed: 11/20/2022] Open
Abstract
In order to identify the mechanism responsible for the formation of charge-density waves (CDW) in cuprate superconductors, it is important to understand which aspects of the CDW's microscopic structure are generic and which are material-dependent. Here, we show that, at the local scale probed by NMR, long-range CDW order in YBa2Cu3Oy is unidirectional with a commensurate period of three unit cells (λ = 3b), implying that the incommensurability found in X-ray scattering is ensured by phase slips (discommensurations). Furthermore, NMR spectra reveal a predominant oxygen character of the CDW with an out-of-phase relationship between certain lattice sites but no specific signature of a secondary CDW with λ = 6b associated with a putative pair-density wave. These results shed light on universal aspects of the cuprate CDW. In particular, its spatial profile appears to generically result from the interplay between an incommensurate tendency at long length scales, possibly related to properties of the Fermi surface, and local commensuration effects, due to electron-electron interactions or lock-in to the lattice.
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Affiliation(s)
- Igor Vinograd
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France.
| | - Rui Zhou
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, Beijing, China
| | - Michihiro Hirata
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France
- MPA-Q, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Tao Wu
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, China
| | - Hadrien Mayaffre
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France
| | - Steffen Krämer
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France
| | - Ruixing Liang
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada
- Canadian Institute for Advanced Research, Toronto, Canada
| | - W N Hardy
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada
- Canadian Institute for Advanced Research, Toronto, Canada
| | - D A Bonn
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada
- Canadian Institute for Advanced Research, Toronto, Canada
| | - Marc-Henri Julien
- Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, EMFL, CNRS, LNCMI, Grenoble, France.
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10
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McMahon C, Achkar AJ, da Silva Neto EH, Djianto I, Menard J, He F, Sutarto R, Comin R, Liang R, Bonn DA, Hardy WN, Damascelli A, Hawthorn DG. Orbital symmetries of charge density wave order in YBa 2Cu 3O 6+x. SCIENCE ADVANCES 2020; 6:6/45/eaay0345. [PMID: 33158874 PMCID: PMC7673704 DOI: 10.1126/sciadv.aay0345] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 09/24/2020] [Indexed: 06/11/2023]
Abstract
Charge density wave (CDW) order has been shown to compete and coexist with superconductivity in underdoped cuprates. Theoretical proposals for the CDW order include an unconventional d-symmetry form factor CDW, evidence for which has emerged from measurements, including resonant soft x-ray scattering (RSXS) in YBa2Cu3O6+x (YBCO). Here, we revisit RSXS measurements of the CDW symmetry in YBCO, using a variation in the measurement geometry to provide enhanced sensitivity to orbital symmetry. We show that the (0 0.31 L) CDW peak measured at the Cu L edge is dominated by an s form factor rather than a d form factor as was reported previously. In addition, by measuring both (0.31 0 L) and (0 0.31 L) peaks, we identify a pronounced difference in the orbital symmetry of the CDW order along the a and b axes, with the CDW along the a axis exhibiting orbital order in addition to charge order.
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Affiliation(s)
- Christopher McMahon
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - A J Achkar
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - E H da Silva Neto
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- CIFAR, Toronto, Ontario M5G 1Z8, Canada
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
- Department of Physics, University of California, Davis, CA 95616, USA
- Department of Physics, Yale University, New Haven, CT 06511, USA
| | - I Djianto
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - J Menard
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - F He
- Canadian Light Source, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - R Sutarto
- Canadian Light Source, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - R Comin
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ruixing Liang
- CIFAR, Toronto, Ontario M5G 1Z8, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - D A Bonn
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- CIFAR, Toronto, Ontario M5G 1Z8, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - W N Hardy
- CIFAR, Toronto, Ontario M5G 1Z8, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - A Damascelli
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- CIFAR, Toronto, Ontario M5G 1Z8, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - D G Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
- CIFAR, Toronto, Ontario M5G 1Z8, Canada
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11
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Zhang H, Hao L, Yang J, Mutch J, Liu Z, Huang Q, Noordhoek K, May AF, Chu JH, Kim JW, Ryan PJ, Zhou H, Liu J. Comprehensive Electrical Control of Metamagnetic Transition of a Quasi-2D Antiferromagnet by In Situ Anisotropic Strain. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2002451. [PMID: 32697370 DOI: 10.1002/adma.202002451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Effective nonmagnetic control of the spin structure is at the forefront of the study for functional quantum materials. This study demonstrates that, by applying an anisotropic strain up to only 0.05%, the metamagnetic transition field of spin-orbit-coupled Mott insulator Sr2 IrO4 can be in situ modulated by almost 300%. Simultaneous measurements of resonant X-ray scattering and transport reveal that this drastic response originates from the complete strain-tuning of the transition between the spin-flop and spin-flip limits, and is always accompanied by large elastoconductance and magnetoconductance. This enables electrically controllable and electronically detectable metamagnetic switching, despite the antiferromagnetic insulating state. The obtained strain-magnetic field phase diagram reveals that C4 -symmetry-breaking anisotropy is introduced by strain via pseudospin-lattice coupling, directly demonstrating the pseudo-Jahn-Teller effect of spin-orbit-coupled complex oxides. The extracted coupling strength is much weaker than the superexchange interactions, yet crucial for the spontaneous symmetry-breaking, affording the remarkably efficient strain-control.
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Affiliation(s)
- Han Zhang
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
| | - Lin Hao
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
| | - Junyi Yang
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
| | - Josh Mutch
- Department of Physics, University of Washington, Seattle, WA, 98195, USA
| | - Zhaoyu Liu
- Department of Physics, University of Washington, Seattle, WA, 98195, USA
| | - Qing Huang
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
| | - Kyle Noordhoek
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
| | - Andrew F May
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Jiun-Haw Chu
- Department of Physics, University of Washington, Seattle, WA, 98195, USA
| | - Jong-Woo Kim
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Philip J Ryan
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
- School of Physical Sciences, Dublin City University, Dublin 11, Ireland
| | - Haidong Zhou
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
| | - Jian Liu
- Department of Physics and Astronomy, The University of Tennessee, 217A A. H. Nielsen Physics Building, Knoxville, TN, 37996, USA
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12
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Multiorbital charge-density wave excitations and concomitant phonon anomalies in Bi 2Sr 2LaCuO 6+δ. Proc Natl Acad Sci U S A 2020; 117:16219-16225. [PMID: 32586955 PMCID: PMC7368327 DOI: 10.1073/pnas.2001755117] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Charge-density waves (CDWs) are a ubiquitous form of electron density modulation in cuprate superconductors. Unveiling the nature of quasistatic CDWs and their dynamical excitations is crucial for understanding their origin––similar to the study of antiferromagnetism in cuprates. However, dynamical CDW excitations remain largely unexplored due to the limited availability of suitable experimental probes. Here, using resonant inelastic X-ray scattering, we observe dynamical CDW excitations in Bi2Sr2LaCuO6+δ (Bi2201) superconductors through its interference with the lattice. The distinct anomalies of the bond-buckling and the bond-stretching phonons allow us to draw a clear picture of funnel-shaped dynamical CDW excitations in Bi2201. Our results of the interplay between CDWs and the phonon anomalies shed light on the nature of CDWs in cuprates. Charge-density waves (CDWs) are ubiquitous in underdoped cuprate superconductors. As a modulation of the valence electron density, CDWs in hole-doped cuprates possess both Cu-3d and O-2p orbital character owing to the strong hybridization of these orbitals near the Fermi level. Here, we investigate underdoped Bi2Sr1.4La0.6CuO6+δ using resonant inelastic X-ray scattering (RIXS) and find that a short-range CDW exists at both Cu and O sublattices in the copper-oxide (CuO2) planes with a comparable periodicity and correlation length. Furthermore, we uncover bond-stretching and bond-buckling phonon anomalies concomitant to the CDWs. Comparing to slightly overdoped Bi2Sr1.8La0.2CuO6+δ, where neither CDWs nor phonon anomalies appear, we highlight that a sharp intensity anomaly is induced in the proximity of the CDW wavevector (QCDW) for the bond-buckling phonon, in concert with the diffused intensity enhancement of the bond-stretching phonon at wavevectors much greater than QCDW. Our results provide a comprehensive picture of the quasistatic CDWs, their dispersive excitations, and associated electron-phonon anomalies, which are key for understanding the competing electronic instabilities in cuprates.
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13
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Frano A, Blanco-Canosa S, Keimer B, Birgeneau RJ. Charge ordering in superconducting copper oxides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:374005. [PMID: 31829986 DOI: 10.1088/1361-648x/ab6140] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Charge order has recently been identified as a leading competitor of high-temperature superconductivity in moderately doped cuprates. We provide a survey of universal and materials-specific aspects of this phenomenon, with emphasis on results obtained by scattering methods. In particular, we discuss the structure, periodicity, and stability range of the charge-ordered state, its response to various external perturbations, the influence of disorder, the coexistence and competition with superconductivity, as well as collective charge dynamics. In the context of this journal issue which honors Roger Cowley's legacy, we also discuss the connection of charge ordering with lattice vibrations and the central-peak phenomenon. We end the review with an outlook on research opportunities offered by new synthesis methods and experimental platforms, including cuprate thin films and superlattices.
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Affiliation(s)
- Alex Frano
- Department of Physics, University of California, San Diego, CA 92093, United States of America
| | - Santiago Blanco-Canosa
- Donostia International Physics Center, DIPC, 20018 Donostia-San Sebastian, Basque Country, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Basque Country, Spain
| | - Bernhard Keimer
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
| | - Robert J Birgeneau
- Department of Physics, University of California, Berkeley, CA 94720, United States of America
- Department of Materials Science and Engineering, University of California Berkeley, Berkeley, CA 94720, United States of America
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14
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Cho CW, Shen J, Lyu J, Atanov O, Chen Q, Lee SH, Hor YS, Gawryluk DJ, Pomjakushina E, Bartkowiak M, Hecker M, Schmalian J, Lortz R. Z 3-vestigial nematic order due to superconducting fluctuations in the doped topological insulators Nb xBi 2Se 3 and Cu xBi 2Se 3. Nat Commun 2020; 11:3056. [PMID: 32546839 PMCID: PMC7298044 DOI: 10.1038/s41467-020-16871-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 05/29/2020] [Indexed: 12/04/2022] Open
Abstract
A state of matter with a multi-component order parameter can give rise to vestigial order. In the vestigial phase, the primary order is only partially melted, leaving a remaining symmetry breaking behind, an effect driven by strong classical or quantum fluctuations. Vestigial states due to primary spin and charge-density-wave order have been discussed in iron-based and cuprate materials. Here we present the observation of a partially melted superconductivity in which pairing fluctuations condense at a separate phase transition and form a nematic state with broken Z3, i.e., three-state Potts-model symmetry. Thermal expansion, specific heat and magnetization measurements of the doped topological insulators NbxBi2Se3 and CuxBi2Se3 reveal that this symmetry breaking occurs at [Formula: see text] above [Formula: see text], along with an onset of superconducting fluctuations. Thus, before Cooper pairs establish long-range coherence at Tc, they fluctuate in a way that breaks the rotational invariance at Tnem and induces a crystalline distortion.
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Affiliation(s)
- Chang-Woo Cho
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Junying Shen
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
- Laboratory for Neutron and Muon Instrumentation, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Jian Lyu
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Omargeldi Atanov
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Qianxue Chen
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Seng Huat Lee
- Department of Physics, Missouri University of Science and Technology, Rolla, MO, 65409, USA
- 2D Crystal Consortium, Materials Research Institute, Pennsylvania State University, University Park, PA, 16802, USA
| | - Yew San Hor
- Department of Physics, Missouri University of Science and Technology, Rolla, MO, 65409, USA
| | - Dariusz Jakub Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland
| | - Marek Bartkowiak
- Laboratory for Neutron and Muon Instrumentation, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Matthias Hecker
- Institute for Theory of Condensed Matter and Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Jörg Schmalian
- Institute for Theory of Condensed Matter and Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Rolf Lortz
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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15
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Hosur PR. Time-reversal asymmetry without local moments via directional scalar spin chirality. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:255604. [PMID: 32106103 DOI: 10.1088/1361-648x/ab7ad9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Invariably, time-reversal symmetry (TRS) violation in a state of matter is identified with static magnetism in it. Here, a directional scalar spin chiral order (DSSCO) phase is introduced that disobeys this basic principle: it breaks TRS but has no density of static moments. It can be obtained by melting the spin moments in a magnetically ordered phase but retaining residual broken TRS. Orbital moments are then precluded by the spatial symmetries of the spin rotation symmetric state. It is allowed in one, two and three dimensions under different conditions of temperature and disorder. Recently, polar Kerr effect experiments in the mysterious pseudogap phase of the underdoped cuprates hinted at a strange form of broken TRS below a temperature T K, that exhibits a hysteretic 'memory effect' above T K and begs reconciliation with nuclear magnetic resonance (which sees no moments), x-ray diffraction (which finds charge ordering tendencies) and the Nernst effect (which detects nematicity). Remarkably, the DSSCO provides a phenomenological route for reconciling all these observations, and it is conceivable that it onsets at the pseudogap temperature ∼T*. A six-spin interaction mediated by enhanced fluctuations of velocity asymmetry between left- and right-movers above the onset of charge ordering in the cuprates is proposed as the driving force behind DSSCO formation. A testable prediction of the existence of the DSSCO in the cuprates is a Kerr signal above T K triggered and trainable by a current driven along one of the in-plane axes, but not by a current along the other.
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Affiliation(s)
- Pavan R Hosur
- Department of Physics, University of Houston, Houston, 77204, United States of America
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16
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Zhang Y, Lane C, Furness JW, Barbiellini B, Perdew JP, Markiewicz RS, Bansil A, Sun J. Competing stripe and magnetic phases in the cuprates from first principles. Proc Natl Acad Sci U S A 2020; 117:68-72. [PMID: 31843896 PMCID: PMC6955329 DOI: 10.1073/pnas.1910411116] [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
Realistic description of competing phases in complex quantum materials has proven extremely challenging. For example, much of the existing density-functional-theory-based first-principles framework fails in the cuprate superconductors. Various many-body approaches involve generic model Hamiltonians and do not account for the interplay between the spin, charge, and lattice degrees of freedom. Here, by deploying the recently constructed strongly constrained and appropriately normed (SCAN) density functional, we show how the landscape of competing stripe and magnetic phases can be addressed on a first-principles basis both in the parent insulator YBa2Cu3O6 and the near-optimally doped YBa2Cu3O7 as archetype cuprate compounds. In YBa2Cu3O7, we find many stripe phases that are nearly degenerate with the ground state and may give rise to the pseudogap state from which the high-temperature superconducting state emerges. We invoke no free parameters such as the Hubbard U, which has been the basis of much of the existing cuprate literature. Lattice degrees of freedom are found to be crucially important in stabilizing the various phases.
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Affiliation(s)
- Yubo Zhang
- Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118
| | - Christopher Lane
- Department of Physics, Northeastern University, Boston, MA 02115
| | - James W Furness
- Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118
| | - Bernardo Barbiellini
- Department of Physics, School of Engineering Science, LUT University, FI-53851 Lappeenranta, Finland
- Department of Physics, Northeastern University, Boston, MA 02115
| | - John P Perdew
- Department of Physics, Temple University, Philadelphia, PA 19122;
- Department of Chemistry, Temple University, Philadelphia, PA 19122
| | | | - Arun Bansil
- Department of Physics, Northeastern University, Boston, MA 02115;
| | - Jianwei Sun
- Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118;
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17
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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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18
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Rogge PC, Shafer P, Fabbris G, Hu W, Arenholz E, Karapetrova E, Dean MPM, Green RJ, May SJ. Depth-Resolved Modulation of Metal-Oxygen Hybridization and Orbital Polarization across Correlated Oxide Interfaces. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1902364. [PMID: 31515864 DOI: 10.1002/adma.201902364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 08/22/2019] [Indexed: 06/10/2023]
Abstract
Interface-induced modifications of the electronic, magnetic, and lattice degrees of freedom drive an array of novel physical properties in oxide heterostructures. Here, large changes in metal-oxygen band hybridization, as measured in the oxygen ligand hole density, are induced as a result of interfacing two isovalent correlated oxides. Using resonant X-ray reflectivity, a superlattice of SrFeO3 and CaFeO3 is shown to exhibit an electronic character that spatially evolves from strongly O-like in SrFeO3 to strongly Fe-like in CaFeO3 . This alternating degree of Fe electronic character is correlated with a modulation of an Fe 3d orbital polarization, giving rise to an orbital superstructure. At the SrFeO3 /CaFeO3 interfaces, the ligand hole density and orbital polarization reconstruct in a single unit cell of CaFeO3 , demonstrating how the mismatch in these electronic parameters is accommodated at the interface. These results provide new insight into how the orbital character of electrons is altered by correlated oxide interfaces and lays out a broadly applicable approach for depth-resolving band hybridization.
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Affiliation(s)
- Paul C Rogge
- Department of Materials Science and Engineering, Drexel University, 3141 Chestnut St., Philadelphia, PA, 19104, USA
| | - Padraic Shafer
- Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, USA
| | - Gilberto Fabbris
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, 98 Rochester St., Upton, NY, 11973, USA
| | - Wen Hu
- National Synchrotron Light Source II, Brookhaven National Laboratory, 98 Rochester St., Upton, NY, 11973, USA
| | - Elke Arenholz
- Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, USA
- Cornell High Energy Synchrotron Source, Cornell University, 161 Wilson Laboratory, Synchrotron Drive, Ithaca, NY, 14853, USA
| | - Evguenia Karapetrova
- Advanced Photon Source, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL, 60439, USA
| | - Mark P M Dean
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, 98 Rochester St., Upton, NY, 11973, USA
| | - Robert J Green
- Department of Physics and Engineering Physics, University of Saskatchewan, 116 Science Pl, Saskatoon, Saskatchewan, S7N 5E2, Canada
- Stewart Blusson Quantum Matter Institute, University of British Columbia, 111-2355 E Mall, Vancouver, British Columbia, V6T 1Z4, Canada
| | - Steven J May
- Department of Materials Science and Engineering, Drexel University, 3141 Chestnut St., Philadelphia, PA, 19104, USA
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19
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Charge order and broken rotational symmetry in magic-angle twisted bilayer graphene. Nature 2019; 573:91-95. [DOI: 10.1038/s41586-019-1460-4] [Citation(s) in RCA: 349] [Impact Index Per Article: 69.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/16/2019] [Indexed: 11/09/2022]
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20
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Myasnikova AE, Nazdracheva TF, Lutsenko AV, Dmitriev AV, Dzhantemirov AH, Zhileeva EA, Moseykin DV. Strong long-range electron-phonon interaction as possible driving force for charge ordering in cuprates. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:235602. [PMID: 30840947 DOI: 10.1088/1361-648x/ab0d6c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A model resulting in charge ordering (CO) similar to that observed in cuprate superconductors is under study. It includes strong long-range electron-phonon interaction (EPI) and high density of correlated carriers. Coexistence of large bipolarons and delocalized carriers is a feature of such system. We develop generalized variation method to calculate the bipolaron size (CO period) in the ground normal state of such system at various doping. The approach allows the revealing of a possible physical reason of strongly different doping behavior of the CO wave vector in different cuprates. Obtained doping dependences of the CO period and temperature of the CO decay demonstrate quantitative agreement with those observed in cuprates. Predicted in the suggested approach ratio of the CO wave vector to the wave vector of the high-energy anomaly (HEA) in ARPES spectrum is in consent with that in cuprates. Calculated resonant x-rays scattering on the CO emerging in the model is in good agreement with experiments on cuprates including the asymmetry of the CO peaks' cross-section. A gap arises in the spectrum of delocalized carriers near antinodal direction due to their scattering on the periodic potential created by autolocalized carriers, analogously to photon crystal effect.
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21
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Evidence for a vestigial nematic state in the cuprate pseudogap phase. Proc Natl Acad Sci U S A 2019; 116:13249-13254. [PMID: 31160468 DOI: 10.1073/pnas.1821454116] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The CuO2 antiferromagnetic insulator is transformed by hole-doping into an exotic quantum fluid usually referred to as the pseudogap (PG) phase. Its defining characteristic is a strong suppression of the electronic density-of-states D(E) for energies |E| < [Formula: see text], where [Formula: see text] is the PG energy. Unanticipated broken-symmetry phases have been detected by a wide variety of techniques in the PG regime, most significantly a finite-Q density-wave (DW) state and a Q = 0 nematic (NE) state. Sublattice-phase-resolved imaging of electronic structure allows the doping and energy dependence of these distinct broken-symmetry states to be visualized simultaneously. Using this approach, we show that even though their reported ordering temperatures T DW and T NE are unrelated to each other, both the DW and NE states always exhibit their maximum spectral intensity at the same energy, and using independent measurements that this is the PG energy [Formula: see text] Moreover, no new energy-gap opening coincides with the appearance of the DW state (which should theoretically open an energy gap on the Fermi surface), while the observed PG opening coincides with the appearance of the NE state (which should theoretically be incapable of opening a Fermi-surface gap). We demonstrate how this perplexing phenomenology of thermal transitions and energy-gap opening at the breaking of two highly distinct symmetries may be understood as the natural consequence of a vestigial nematic state within the pseudogap phase of Bi2Sr2CaCu2O8.
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22
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Deng S, Wu L, Cheng H, Zheng JC, Cheng S, Li J, Wang W, Shen J, Tao J, Zhu J, Zhu Y. Charge-Lattice Coupling in Hole-Doped LuFe_{2}O_{4+δ}: The Origin of Second-Order Modulation. PHYSICAL REVIEW LETTERS 2019; 122:126401. [PMID: 30978042 DOI: 10.1103/physrevlett.122.126401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 01/20/2019] [Indexed: 06/09/2023]
Abstract
Understanding singularities in ordered structures, such as dislocations in lattice modulation and solitons in charge ordering, offers great opportunities to disentangle the interactions between the electronic degrees of freedom and the lattice. Specifically, a modulated structure has traditionally been expressed in the form of a discrete Fourier series with a constant phase and amplitude for each component. Here, we report atomic scale observation and analysis of a new modulation wave in hole-doped LuFe_{2}O_{4+δ} that requires significant modifications to the conventional modeling of ordered structures. This new modulation with an unusual quasiperiodic singularity can be accurately described only by introducing a well-defined secondary modulation vector in both the phase and amplitude parameter spaces. Correlated with density-functional-theory (DFT) calculations, our results reveal that those singularities originate from the discontinuity of lattice displacement induced by interstitial oxygen in the system. The approach of our work is applicable to a wide range of ordered systems, advancing our understanding of the nature of singularity and modulation.
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Affiliation(s)
- Shiqing Deng
- School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Lijun Wu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Hao Cheng
- Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China
| | - Jin-Cheng Zheng
- Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China
| | - Shaobo Cheng
- School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Jun Li
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Wenbin Wang
- Institute of Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai 200433, People's Republic of China
| | - Jian Shen
- Department of Physics, Fudan University, Shanghai 200433, People's Republic of China
| | - Jing Tao
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Jing Zhu
- School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yimei Zhu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
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23
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Tu WL, Lee TK. Evolution of Pairing Orders between Pseudogap and Superconducting Phases of Cuprate Superconductors. Sci Rep 2019; 9:1719. [PMID: 30737472 PMCID: PMC6368576 DOI: 10.1038/s41598-018-38288-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 12/10/2018] [Indexed: 11/09/2022] Open
Abstract
One of the most puzzling problems of high temperature cuprate superconductor is the pseudogap phase (PG) at temperatures above the superconducting transition temperature in the underdoped regime. The PG phase is found by the angle-resolved photoemission spectra (ARPES) to have a gap at some regions in momentum space and a fraction of Fermi surface remained, known as Fermi arcs. The arc turns into a d-wave SC gap with a node below the SC transition temperature. Here, by studying a strongly correlated model at low temperatures, we obtained a phase characterized by two kinds of pairing order parameters with the total momentum of the Cooper pair to be zero and finite. The finite momentum pairing is accompanied with a spatial modulation of pairing order, i.e. a pair density wave (PDW). These PDW phases are intertwined with modulations of charge density and intra-unit cell form factors. The coexistence of the two different pairing orders provides the unique two-gaps like spectra observed by ARPES for superconducting cuprates. As temperature raises, the zero-momentum pairing order vanishes while the finite momentum pairing orders are kept, thus Fermi arcs are realized. The calculated quasiparticle spectra have the similar doping and temperature dependence as reported by ARPES and scanning tunneling spectroscopy (STS). The consequence of breaking symmetry between x and y due to the unidirectional PDW and the possibility to probe such a PDW state in the PG phase is discussed.
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Affiliation(s)
- Wei-Lin Tu
- Department of Physics, National Taiwan University, Daan, Taipei, 10617, Taiwan
- Laboratoire de Physique Théorique, IRSAMC, Université de Toulouse, CNRS, UPS, Toulouse, France
- Institute of Physics, Academia Sinica, Nankang, Taipei, 11529, Taiwan
| | - Ting-Kuo Lee
- Institute of Physics, Academia Sinica, Nankang, Taipei, 11529, Taiwan.
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Pelc D, Popčević P, Požek M, Greven M, Barišić N. Unusual behavior of cuprates explained by heterogeneous charge localization. SCIENCE ADVANCES 2019; 5:eaau4538. [PMID: 30746450 PMCID: PMC6357730 DOI: 10.1126/sciadv.aau4538] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 12/07/2018] [Indexed: 06/09/2023]
Abstract
The discovery of high-temperature superconductivity in cuprates ranks among the major scientific milestones of the past half century, yet pivotal questions regarding the complex phase diagram of these materials remain unanswered. Generally thought of as doped charge-transfer insulators, these complex oxides exhibit pseudogap, strange-metal, superconducting, and Fermi liquid behavior with increasing hole-dopant concentration. Motivated by recent experimental observations, here we introduce a phenomenological model wherein exactly one hole per planar copper-oxygen unit is delocalized with increasing doping and temperature. The model is percolative in nature, with parameters that are highly consistent with experiments. It comprehensively captures key unconventional experimental results, including the temperature and the doping dependence of the pseudogap phenomenon, the strange-metal linear temperature dependence of the planar resistivity, and the doping dependence of the superfluid density. The success and simplicity of the model greatly demystify the cuprate phase diagram and point to a local superconducting pairing mechanism.
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Affiliation(s)
- D. Pelc
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - P. Popčević
- Institute of Solid State Physics, TU Wien, 1040 Vienna, Austria
- Institute of Physics, HR-10000 Zagreb, Croatia
| | - M. Požek
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
| | - M. Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - N. Barišić
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
- Institute of Solid State Physics, TU Wien, 1040 Vienna, Austria
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Peng YY, Fumagalli R, Ding Y, Minola M, Caprara S, Betto D, Bluschke M, De Luca GM, Kummer K, Lefrançois E, Salluzzo M, Suzuki H, Le Tacon M, Zhou XJ, Brookes NB, Keimer B, Braicovich L, Grilli M, Ghiringhelli G. Re-entrant charge order in overdoped (Bi,Pb) 2.12Sr 1.88CuO 6+δ outside the pseudogap regime. NATURE MATERIALS 2018; 17:697-702. [PMID: 29891891 DOI: 10.1038/s41563-018-0108-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 05/14/2018] [Indexed: 06/08/2023]
Abstract
In the underdoped regime, the cuprate high-temperature superconductors exhibit a host of unusual collective phenomena, including unconventional spin and charge density modulations, Fermi surface reconstructions, and a pseudogap in various physical observables. Conversely, overdoped cuprates are generally regarded as conventional Fermi liquids possessing no collective electronic order. In partial contradiction to this widely held picture, we report resonant X-ray scattering measurements revealing incommensurate charge order reflections for overdoped (Bi,Pb)2.12Sr1.88CuO6+δ (Bi2201), with correlation lengths of 40-60 lattice units, that persist up to temperatures of at least 250 K. The value of the charge order wavevector decreases with doping, in line with the extrapolation of the trend previously observed in underdoped Bi2201. In overdoped materials, however, charge order coexists with a single, unreconstructed Fermi surface without nesting or pseudogap features. The discovery of re-entrant charge order in Bi2201 thus calls for investigations in other cuprate families and for a reconsideration of theories that posit an essential relationship between these phenomena.
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Affiliation(s)
- Y Y Peng
- Dipartimento di Fisica, Politecnico di Milano, Milano, Italy
- Department of Physics and Seitz Materials Research Laboratory, University of Illinois, Urbana, IL, USA
| | - R Fumagalli
- Dipartimento di Fisica, Politecnico di Milano, Milano, Italy
| | - Y Ding
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - M Minola
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
| | - S Caprara
- Dipartimento di Fisica, Università di Roma 'La Sapienza', Roma, Italy
- CNR-ISC, Roma, Italy
| | - D Betto
- ESRF, The European Synchrotron, Grenoble, France
| | - M Bluschke
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
| | - G M De Luca
- Dipartimento di Fisica 'E. Pancini', Università di Napoli Federico II, Napoli, Italy
- CNR-SPIN, Napoli, Italy
| | - K Kummer
- ESRF, The European Synchrotron, Grenoble, France
| | - E Lefrançois
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
| | | | - H Suzuki
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
| | - M Le Tacon
- Institute of Solid State Physics (IFP), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - X J Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - N B Brookes
- ESRF, The European Synchrotron, Grenoble, France
| | - B Keimer
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
| | - L Braicovich
- Dipartimento di Fisica, Politecnico di Milano, Milano, Italy
- ESRF, The European Synchrotron, Grenoble, France
| | - M Grilli
- Dipartimento di Fisica, Università di Roma 'La Sapienza', Roma, Italy
- CNR-ISC, Roma, Italy
| | - G Ghiringhelli
- Dipartimento di Fisica, Politecnico di Milano, Milano, Italy.
- CNR-SPIN, Dipartimento di Fisica, Politecnico di Milano, Milano, Italy.
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Morice C, Chakraborty D, Montiel X, Pépin C. Pseudo-spin skyrmions in the phase diagram of cuprate superconductors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:295601. [PMID: 29947331 DOI: 10.1088/1361-648x/aacc0f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Topological states of matter are at the root of some of the most fascinating phenomena in condensed matter physics. Here we argue that skyrmions in the pseudo-spin space related to an emerging SU(2) symmetry enlighten many mysterious properties of the pseudogap phase in under-doped cuprates. We detail the role of the SU(2) symmetry in controlling the phase diagram of the cuprates, in particular how a cascade of phase transitions explains the arising of the pseudogap, superconducting and charge modulation phases seen at low temperature. We specify the structure of the charge modulations inside the vortex core below T c, as well as in a wide temperature region above T c, which is a signature of the skyrmion topological structure. We argue that the underlying SU(2) symmetry is the main structure controlling the emergent complexity of excitations at the pseudogap scale T *. The theory yields a gapping of a large part of the anti-nodal region of the Brillouin zone, along with q = 0 phase transitions, of both nematic and loop currents characters.
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Affiliation(s)
- C Morice
- Institut de Physique Théorique, CEA, Université Paris-Saclay, Saclay, France
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27
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Vishik IM. Photoemission perspective on pseudogap, superconducting fluctuations, and charge order in cuprates: a review of recent progress. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:062501. [PMID: 29595144 DOI: 10.1088/1361-6633/aaba96] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the course of seeking the microscopic mechanism of superconductivity in cuprate high temperature superconductors, the pseudogap phase- the very abnormal 'normal' state on the hole-doped side- has proven to be as big of a quandary as superconductivity itself. Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool for assessing the momentum-dependent phenomenology of the pseudogap, and recent technological developments have permitted a more detailed understanding. This report reviews recent progress in understanding the relationship between superconductivity and the pseudogap, the Fermi arc phenomena, and the relationship between charge order and pseudogap from the perspective of ARPES measurements.
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Affiliation(s)
- I M Vishik
- University of California, Davis, CA 95616, United States of America
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28
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Ekino T, Gabovich AM, Suan Li M, Szymczak H, Voitenko AI. Quasiparticle conductance-voltage characteristics for break junctions involving d-wave superconductors: charge-density-wave effects. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:505602. [PMID: 29105650 DOI: 10.1088/1361-648x/aa9867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Quasiparticle tunnel conductance-voltage characteristics (CVCs), [Formula: see text], were calculated for break junctions (BJs) made up of layered d-wave superconductors partially gapped by charge-density waves (CDWs). The current is assumed to flow in the ab-plane of electrodes. The influence of CDWs is analyzed by comparing the resulting CVCs with CVCs calculated for BJs made up of pure d-wave superconductors with relevant parameters. The main CDW-effects were found to be the appearance of new CVC peculiarities and the loss of CVC symmetry with respect to the V-sign. Tunnel directionality was shown to be one of the key factors in the formation of [Formula: see text] dependences. In particular, the orientation of electrodes with respect to the current channel becomes very important. As a result, [Formula: see text] can acquire a large variety of forms similar to those for tunnel junctions between superconductors with s-wave, d-wave, and mixed symmetry of their order parameters. The diversity of peculiarities is especially striking at finite temperatures. In the case of BJs made up of pure d-wave superconductors, the resulting CVC can include a two-peak gap-driven structure. The results were compared with the experimental BJ data for a number of high-T c oxides. It was shown that the large variety of the observed current-voltage characteristics can be interpreted in the framework of our approach. Thus, quasiparticle tunnel currents in the ab-plane can be used as an additional mean to detect CDWs competing with superconductivity in cuprates or other layered superconductors.
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Affiliation(s)
- T Ekino
- Hiroshima University, Graduate School of Integrated Arts and Sciences, Higashi-Hiroshima, 739-8521, Japan
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29
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Kawasaki S, Li Z, Kitahashi M, Lin CT, Kuhns PL, Reyes AP, Zheng GQ. Charge-density-wave order takes over antiferromagnetism in Bi 2Sr 2-x La x CuO 6 superconductors. Nat Commun 2017; 8:1267. [PMID: 29097672 PMCID: PMC5668353 DOI: 10.1038/s41467-017-01465-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 09/19/2017] [Indexed: 11/17/2022] Open
Abstract
Superconductivity appears in the cuprates when a spin order is destroyed, while the role of charge is less known. Recently, charge density wave (CDW) was found below the superconducting dome in YBa2Cu3Oy when a high magnetic field is applied perpendicular to the CuO2 plane, which was suggested to arise from incipient CDW in the vortex cores that becomes overlapped. Here by 63Cu-nuclear magnetic resonance, we report the discovery of CDW induced by an in-plane field, setting in above the dome in single-layered Bi2Sr2−xLaxCuO6. The onset temperature TCDW takes over the antiferromagnetic order temperature TN beyond a critical doping level at which superconductivity starts to emerge, and scales with the pseudogap temperature T*. These results provide important insights into the relationship between spin order, CDW and the pseudogap, and their connections to high-temperature superconductivity. Whilst superconductivity usually appears when magnetic order is suppressed, the role of charge is less known. Here, Kawasaki et al. report a charge density wave (CDW) above the superconducting transition induced by an in-plane magnetic field in Bi2Sr2-xLaxCuO6, with the CDW onset temperature scaling with the pseudogap temperature.
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Affiliation(s)
- S Kawasaki
- Department of Physics, Okayama University, Okayama, 700-8530, Japan
| | - Z Li
- Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, 100190, Beijing, China
| | - M Kitahashi
- Department of Physics, Okayama University, Okayama, 700-8530, Japan
| | - C T Lin
- Max-Planck-Institut fur Festkorperforschung, Heisenbergstrasse 1, D-70569, Stuttgart, Germany
| | - P L Kuhns
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - A P Reyes
- National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Guo-Qing Zheng
- Department of Physics, Okayama University, Okayama, 700-8530, Japan. .,Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics, 100190, Beijing, China.
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30
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Caplan Y, Orgad D. Dimensional Crossover of Charge-Density Wave Correlations in the Cuprates. PHYSICAL REVIEW LETTERS 2017; 119:107002. [PMID: 28949186 DOI: 10.1103/physrevlett.119.107002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Indexed: 06/07/2023]
Abstract
Short-range charge-density wave correlations are ubiquitous in underdoped cuprates. They are largely confined to the copper-oxygen planes and typically oscillate out of phase from one unit cell to the next in the c direction. Recently, it was found that a considerably longer-range charge-density wave order develops in YBa_{2}Cu_{3}O_{6+x} above a sharply defined crossover magnetic field. This order is more three-dimensional and is in-phase along the c axis. Here, we show that such behavior is a consequence of the conflicting ordering tendencies induced by the disorder potential and the Coulomb interaction, where the magnetic field acts to tip the scales from the former to the latter. We base our conclusion on analytic large-N analysis and Monte Carlo simulations of a nonlinear sigma model of competing superconducting and charge-density wave orders. Our results are in agreement with the observed phenomenology in the cuprates, and we discuss their implications to other members of this family, which have not been measured yet at high magnetic fields.
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Affiliation(s)
- Yosef Caplan
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
| | - Dror Orgad
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
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31
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Local particle-hole pair excitations by SU(2) symmetry fluctuations. Sci Rep 2017; 7:3477. [PMID: 28615633 PMCID: PMC5471275 DOI: 10.1038/s41598-017-01538-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 03/30/2017] [Indexed: 11/24/2022] Open
Abstract
Understanding the pseudo-gap phase which opens in the under-doped regime of cuprate superconductors is one of the most enduring challenges of the physics of these compounds. A depletion in the electronic density of states is observed, which is gapping out part of the Fermi surface, leading to the formation of mysterious lines of massless excitations- the Fermi arcs. Here we give a new theoretical account of the physics of the pseudo-gap phase in terms of the emergence of local patches of particle-hole pairs generated by SU(2) symmetry fluctuations. The proliferation of these local patches accounts naturally for the robustness of the pseudo-gap phase to disturbances like disorder or magnetic field and is shown to gap out part of the Fermi surface, leading to the formation of the Fermi arcs. Most noticeably, we show that these patches induce a modulated charge distribution on the Oxygen atoms, in remarkable agreement with recent X-ray and STM observations.
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32
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Zhou R, Hirata M, Wu T, Vinograd I, Mayaffre H, Krämer S, Horvatić M, Berthier C, Reyes AP, Kuhns PL, Liang R, Hardy WN, Bonn DA, Julien MH. Quasiparticle Scattering off Defects and Possible Bound States in Charge-Ordered YBa_{2}Cu_{3}O_{y}. PHYSICAL REVIEW LETTERS 2017; 118:017001. [PMID: 28106424 DOI: 10.1103/physrevlett.118.017001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Indexed: 06/06/2023]
Abstract
We report the NMR observation of a skewed distribution of ^{17}O Knight shifts when a magnetic field quenches superconductivity and induces long-range charge-density-wave (CDW) order in YBa_{2}Cu_{3}O_{y}. This distribution is explained by an inhomogeneous pattern of the local density of states N(E_{F}) arising from quasiparticle scattering off, yet unidentified, defects in the CDW state. We argue that the effect is most likely related to the formation of quasiparticle bound states, as is known to occur, under specific circumstances, in some metals and superconductors (but not in the CDW state, in general, except for very few cases in 1D materials). These observations should provide insight into the microscopic nature of the CDW, especially regarding the reconstructed band structure and the sensitivity to disorder.
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Affiliation(s)
- R Zhou
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - M Hirata
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - T Wu
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - I Vinograd
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - H Mayaffre
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - S Krämer
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - M Horvatić
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - C Berthier
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-UPS-INSA-EMFL, 38042 Grenoble, France
| | - A P Reyes
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - P L Kuhns
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - R Liang
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto M5G 1Z8, Canada
| | - W N Hardy
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto M5G 1Z8, Canada
| | - D A Bonn
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto M5G 1Z8, Canada
| | - M-H Julien
- Laboratoire National des Champs Magnétiques Intenses, CNRS-Université Grenoble Alpes-EMFL, 38042 Grenoble, France
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Ekino T, Gabovich AM, Suan Li M, Szymczak H, Voitenko AI. Influence of the spatially inhomogeneous gap distribution on the quasiparticle current in c-axis junctions involving d-wave superconductors with charge density waves. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:445701. [PMID: 27604150 DOI: 10.1088/0953-8984/28/44/445701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The quasiparticle tunnel current J(V) between the superconducting ab-planes along the c-axis and the corresponding conductance [Formula: see text] were calculated for symmetric junctions composed of disordered d-wave layered superconductors partially gapped by charge density waves (CDWs). Here, V is the voltage. Both the checkerboard and unidirectional CDWs were considered. It was shown that the spatial spread of the CDW-pairing strength substantially smears the peculiarities of G(V) appropriate to uniform superconductors. The resulting curves G(V) become very similar to those observed for a number of cuprates in intrinsic junctions, e.g. mesas. In particular, the influence of CDWs may explain the peak-dip-hump structures frequently found for high-T c oxides.
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Affiliation(s)
- T Ekino
- Hiroshima University, Graduate School of Integrated Arts and Sciences, Higashi-Hiroshima, 739-8521, Japan
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34
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Eberlein A, Metzner W, Sachdev S, Yamase H. Fermi Surface Reconstruction and Drop in the Hall Number due to Spiral Antiferromagnetism in High-T_{c} Cuprates. PHYSICAL REVIEW LETTERS 2016; 117:187001. [PMID: 27835021 DOI: 10.1103/physrevlett.117.187001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Indexed: 06/06/2023]
Abstract
We show that a Fermi surface reconstruction due to spiral antiferromagnetic order may explain the rapid change in the Hall number as recently observed near optimal doping in cuprate superconductors [Badoux et al., Nature (London) 531, 210 (2016)]. The single-particle spectral function in the spiral state exhibits hole pockets which look like Fermi arcs due to a strong momentum dependence of the spectral weight. Adding charge-density wave order further reduces the Fermi surface to a single electron pocket. We propose quantum oscillation measurements to distinguish between commensurate and spiral antiferromagnetic order. Similar results apply to certain metals in which topological order replaces antiferromagnetic order.
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Affiliation(s)
- Andreas Eberlein
- Department of Physics, Harvard University, Cambridge Massachusetts 02138, USA
| | - Walter Metzner
- Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany
| | - Subir Sachdev
- Department of Physics, Harvard University, Cambridge Massachusetts 02138, USA
- Perimeter Institute for Theoretical Physics, Waterloo, Ontario, Canada N2L 2Y5
| | - Hiroyuki Yamase
- National Institute for Materials Science, Tsukuba 305-0047, Japan
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35
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Commensurate 4 a0-period charge density modulations throughout the Bi 2Sr 2CaCu 2O 8+x pseudogap regime. Proc Natl Acad Sci U S A 2016; 113:12661-12666. [PMID: 27791157 DOI: 10.1073/pnas.1614247113] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Theories based upon strong real space (r-space) electron-electron interactions have long predicted that unidirectional charge density modulations (CDMs) with four-unit-cell (4a0) periodicity should occur in the hole-doped cuprate Mott insulator (MI). Experimentally, however, increasing the hole density p is reported to cause the conventionally defined wavevector QA of the CDM to evolve continuously as if driven primarily by momentum-space (k-space) effects. Here we introduce phase-resolved electronic structure visualization for determination of the cuprate CDM wavevector. Remarkably, this technique reveals a virtually doping-independent locking of the local CDM wavevector at [Formula: see text] throughout the underdoped phase diagram of the canonical cuprate Bi2Sr2CaCu2O8 These observations have significant fundamental consequences because they are orthogonal to a k-space (Fermi-surface)-based picture of the cuprate CDMs but are consistent with strong-coupling r-space-based theories. Our findings imply that it is the latter that provides the intrinsic organizational principle for the cuprate CDM state.
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36
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Kharkov YA, Sushkov OP. The amplitudes and the structure of the charge density wave in YBCO. Sci Rep 2016; 6:34551. [PMID: 27721385 PMCID: PMC5056359 DOI: 10.1038/srep34551] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 09/14/2016] [Indexed: 11/28/2022] Open
Abstract
We find unknown s- and d-wave amplitudes of the recently discovered charge density wave (CDW) in underdoped cuprates. To do so we perform a combined analysis of experimental data for ortho-II YBa2Cu3Oy. The analysis includes data on nuclear magnetic resonance, resonant inelastic X-ray scattering, and hard X-ray diffraction. The amplitude of doping modulation found in our analysis is 3.5 · 10−3 in a low magnetic field and T = 60 K, the amplitude is 6.5 · 10−3 in a magnetic field of 30T and T = 1.3 K. The values are in units of elementary charge per unit cell of a CuO2 plane. We show that the data rule out a checkerboard pattern, and we also show that the data might rule out mechanisms of the CDW which do not include phonons.
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Affiliation(s)
- Y A Kharkov
- School of Physics, University of New South Wales, Sydney 2052, Australia
| | - O P Sushkov
- School of Physics, University of New South Wales, Sydney 2052, Australia
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Gyenis A, da Silva Neto EH, Sutarto R, Schierle E, He F, Weschke E, Kavai M, Baumbach RE, Thompson JD, Bauer ED, Fisk Z, Damascelli A, Yazdani A, Aynajian P. Quasi-particle interference of heavy fermions in resonant x-ray scattering. SCIENCE ADVANCES 2016; 2:e1601086. [PMID: 27757422 PMCID: PMC5065254 DOI: 10.1126/sciadv.1601086] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 09/16/2016] [Indexed: 06/06/2023]
Abstract
Resonant x-ray scattering (RXS) has recently become an increasingly important tool for the study of ordering phenomena in correlated electron systems. Yet, the interpretation of RXS experiments remains theoretically challenging because of the complexity of the RXS cross section. Central to this debate is the recent proposal that impurity-induced Friedel oscillations, akin to quasi-particle interference signals observed with a scanning tunneling microscope (STM), can lead to scattering peaks in RXS experiments. The possibility that quasi-particle properties can be probed in RXS measurements opens up a new avenue to study the bulk band structure of materials with the orbital and element selectivity provided by RXS. We test these ideas by combining RXS and STM measurements of the heavy fermion compound CeMIn5 (M = Co, Rh). Temperature- and doping-dependent RXS measurements at the Ce-M4 edge show a broad scattering enhancement that correlates with the appearance of heavy f-electron bands in these compounds. The scattering enhancement is consistent with the measured quasi-particle interference signal in the STM measurements, indicating that the quasi-particle interference can be probed through the momentum distribution of RXS signals. Overall, our experiments demonstrate new opportunities for studies of correlated electronic systems using the RXS technique.
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Affiliation(s)
- András Gyenis
- Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA
| | - Eduardo H. da Silva Neto
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
- Quantum Materials Program, Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada
| | - Ronny Sutarto
- Canadian Light Source, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - Enrico Schierle
- Helmholtz-Zentrum Berlin fürMaterialien und Energie, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany
| | - Feizhou He
- Helmholtz-Zentrum Berlin fürMaterialien und Energie, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany
| | - Eugen Weschke
- Helmholtz-Zentrum Berlin fürMaterialien und Energie, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany
| | - Mariam Kavai
- Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, NY 13902, USA
| | | | | | - Eric D. Bauer
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Zachary Fisk
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA 92697, USA
| | - Andrea Damascelli
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Ali Yazdani
- Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA
| | - Pegor Aynajian
- Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, NY 13902, USA
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38
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Superconductor to Mott insulator transition in YBa2Cu3O7/LaCaMnO3 heterostructures. Sci Rep 2016; 6:33184. [PMID: 27627855 PMCID: PMC5024130 DOI: 10.1038/srep33184] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/15/2016] [Indexed: 11/08/2022] Open
Abstract
The superconductor-to-insulator transition (SIT) induced by means such as external magnetic fields, disorder or spatial confinement is a vivid illustration of a quantum phase transition dramatically affecting the superconducting order parameter. In pursuit of a new realization of the SIT by interfacial charge transfer, we developed extremely thin superlattices composed of high Tc superconductor YBa2Cu3O7 (YBCO) and colossal magnetoresistance ferromagnet La0.67Ca0.33MnO3 (LCMO). By using linearly polarized resonant X-ray absorption spectroscopy and magnetic circular dichroism, combined with hard X-ray photoelectron spectroscopy, we derived a complete picture of the interfacial carrier doping in cuprate and manganite atomic layers, leading to the transition from superconducting to an unusual Mott insulating state emerging with the increase of LCMO layer thickness. In addition, contrary to the common perception that only transition metal ions may respond to the charge transfer process, we found that charge is also actively compensated by rare-earth and alkaline-earth metal ions of the interface. Such deterministic control of Tc by pure electronic doping without any hindering effects of chemical substitution is another promising route to disentangle the role of disorder on the pseudo-gap and charge density wave phases of underdoped cuprates.
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39
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Macke S, Hamann-Borrero JE, Green RJ, Keimer B, Sawatzky GA, Haverkort MW. Dynamical Effects in Resonant X-Ray Diffraction. PHYSICAL REVIEW LETTERS 2016; 117:115501. [PMID: 27661698 DOI: 10.1103/physrevlett.117.115501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Indexed: 06/06/2023]
Abstract
Using resonant magnetic diffraction at the Ni L_{2,3} edge in a LaNiO_{3} superlattice, we show that dynamical effects beyond the standard kinematic approximation can drastically modify the resonant scattering cross section. In particular, the combination of extinction and refraction convert maxima to minima in the azimuthal-angle dependence of the diffracted intensity, which is commonly used to determine orbital and magnetic structures by resonant x-ray diffraction. We provide a comprehensive theoretical description of these effects by numerically solving Maxwell's equations in three dimensions. The understanding and description of dynamical diffraction enhances the capabilities of resonant x-ray scattering as a probe of electronic ordering phenomena in solids.
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Affiliation(s)
- S Macke
- Quantum Matter Institute, Physics and Astronomy Department, The Brimacombe Building, 2355 East Mall, Vancouver V6T 1Z4, Canada
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - J E Hamann-Borrero
- Leibniz Institute for Solid State and Materials Research Dresden, Helmholtzstrae 20, 01069 Dresden, Germany
| | - R J Green
- Quantum Matter Institute, Physics and Astronomy Department, The Brimacombe Building, 2355 East Mall, Vancouver V6T 1Z4, Canada
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - B Keimer
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - G A Sawatzky
- Quantum Matter Institute, Physics and Astronomy Department, The Brimacombe Building, 2355 East Mall, Vancouver V6T 1Z4, Canada
| | - M W Haverkort
- Quantum Matter Institute, Physics and Astronomy Department, The Brimacombe Building, 2355 East Mall, Vancouver V6T 1Z4, Canada
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
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40
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Sachdev S. Emergent gauge fields and the high-temperature superconductors. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:rsta.2015.0248. [PMID: 27458260 DOI: 10.1098/rsta.2015.0248] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/17/2016] [Indexed: 06/06/2023]
Abstract
The quantum entanglement of many states of matter can be represented by electric and magnetic fields, much like those found in Maxwell's theory. These fields 'emerge' from the quantum structure of the many-electron state, rather than being fundamental degrees of freedom of the vacuum. I review basic aspects of the theory of emergent gauge fields in insulators in an intuitive manner. In metals, Fermi liquid (FL) theory relies on adiabatic continuity from the free electron state, and its central consequence is the existence of long-lived electron-like quasi-particles around a Fermi surface enclosing a volume determined by the total density of electrons, via the Luttinger theorem. However, long-range entanglement and emergent gauge fields can also be present in metals. I focus on the 'fractionalized Fermi liquid' (FL*) state, which also has long-lived electron-like quasi-particles around a Fermi surface; however, the Luttinger theorem on the Fermi volume is violated, and this requires the presence of emergent gauge fields, and the associated loss of adiabatic continuity with the free electron state. Finally, I present a brief survey of some recent experiments in the hole-doped cuprate superconductors, and interpret the properties of the pseudogap regime in the framework of the FL* theory.This article is part of the themed issue 'Unifying physics and technology in light of Maxwell's equations'.
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Affiliation(s)
- Subir Sachdev
- Department of Physics, Harvard University, Cambridge, MA 02138, USA Perimeter Institute for Theoretical Physics, Waterloo, Ontario, Canada N2L 2Y5
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41
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Achkar AJ, He F, Sutarto R, McMahon C, Zwiebler M, Hücker M, Gu GD, Liang R, Bonn DA, Hardy WN, Geck J, Hawthorn DG. Orbital symmetry of charge-density-wave order in La1.875Ba0.125CuO4 and YBa2Cu3O6.67. NATURE MATERIALS 2016; 15:616-620. [PMID: 26878313 DOI: 10.1038/nmat4568] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
Recent theories of charge-density-wave (CDW) order in high-temperature superconductors have predicted a primarily d CDW orbital symmetry. Here, we report on the orbital symmetry of CDW order in the canonical cuprate superconductors La1.875Ba0.125CuO4 (LBCO) and YBa2Cu3O6.67 (YBCO), using resonant soft X-ray scattering and a model mapped to the CDW orbital symmetry. From measurements sensitive to the O sublattice, we conclude that LBCO has predominantly s' CDW orbital symmetry, in contrast to the d orbital symmetry recently reported in other cuprates. Furthermore, we show for YBCO that the CDW orbital symmetry differs along the a and b crystal axes and that these both differ from LBCO. This work highlights CDW orbital symmetry as an additional key property that distinguishes the different cuprate families. We discuss how the CDW symmetry may be related to the '1/8-anomaly' and to static spin ordering.
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Affiliation(s)
- A J Achkar
- Department of Physics and Astronomy, University of Waterloo, Waterloo N2L 3G1, Canada
| | - F He
- Canadian Light Source, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - R Sutarto
- Canadian Light Source, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - Christopher McMahon
- Department of Physics and Astronomy, University of Waterloo, Waterloo N2L 3G1, Canada
| | - M Zwiebler
- Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstraße 20, 01069 Dresden, Germany
| | - M Hücker
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - G D Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Ruixing Liang
- Department of Physics and Astronomy, University of British Columbia, Vancouver V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada
| | - D A Bonn
- Department of Physics and Astronomy, University of British Columbia, Vancouver V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada
| | - W N Hardy
- Department of Physics and Astronomy, University of British Columbia, Vancouver V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada
| | - J Geck
- Chemistry and Physics of Materials, Paris Lodron University Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria
| | - D G Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo N2L 3G1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada
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42
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Ibuka S, Imai M. Possibility of charge density wave transition in a SrPt2Sb2 superconductor. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:165702. [PMID: 27023674 DOI: 10.1088/0953-8984/28/16/165702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The first-order transition at T(0) = 270 K for the platinum-based SrPt2Sb2 superconductor was investigated using x-ray diffraction and magnetic susceptibility measurements. When polycrystalline SrPt2Sb2 was cooled down through T(0), the structure was transformed from monoclinic to a modulated orthorhombic structure, and no magnetic order was formed, which illustrates the possibility of a charge density wave (CDW) transition at T(0). SrPt2Sb2 can thus be a new example to examine the interplay of CDW and superconductivity in addition to SrPt2As2, BaPt2As2, and LaPt2Si2. It is unique that the average structure of the low-temperature phase has higher symmetry than that of the high-temperature phase.
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43
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Hamidian MH, Edkins SD, Joo SH, Kostin A, Eisaki H, Uchida S, Lawler MJ, Kim EA, Mackenzie AP, Fujita K, Lee J, Davis JCS. Detection of a Cooper-pair density wave in Bi2Sr2CaCu2O8+x. Nature 2016; 532:343-7. [PMID: 27074504 DOI: 10.1038/nature17411] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 02/08/2016] [Indexed: 11/09/2022]
Abstract
The quantum condensate of Cooper pairs forming a superconductor was originally conceived as being translationally invariant. In theory, however, pairs can exist with finite momentum Q, thus generating a state with a spatially modulated Cooper-pair density. Such a state has been created in ultracold (6)Li gas but never observed directly in any superconductor. It is now widely hypothesized that the pseudogap phase of the copper oxide superconductors contains such a 'pair density wave' state. Here we report the use of nanometre-resolution scanned Josephson tunnelling microscopy to image Cooper pair tunnelling from a d-wave superconducting microscope tip to the condensate of the superconductor Bi2Sr2CaCu2O8+x. We demonstrate condensate visualization capabilities directly by using the Cooper-pair density variations surrounding zinc impurity atoms and at the Bi2Sr2CaCu2O8+x crystal supermodulation. Then, by using Fourier analysis of scanned Josephson tunnelling images, we discover the direct signature of a Cooper-pair density modulation at wavevectors QP ≈ (0.25, 0)2π/a0 and (0, 0.25)2π/a0 in Bi2Sr2CaCu2O8+x. The amplitude of these modulations is about five per cent of the background condensate density and their form factor exhibits primarily s or s' symmetry. This phenomenology is consistent with Ginzburg-Landau theory when a charge density wave with d-symmetry form factor and wavevector QC = QP coexists with a d-symmetry superconductor; it is also predicted by several contemporary microscopic theories for the pseudogap phase.
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Affiliation(s)
- M H Hamidian
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - S D Edkins
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.,School of Physics and Astronomy, University of St Andrews, Fife KY16 9SS, UK
| | - Sang Hyun Joo
- Institute of Applied Physics, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, South Korea.,Center for Correlated Electron Systems, Institute of Basic Science, Seoul 151-742, South Korea
| | - A Kostin
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - H Eisaki
- Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan
| | - S Uchida
- Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan.,Department of Physics, University of Tokyo, Bunkyo, Tokyo 113-0011, Japan
| | - M J Lawler
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.,Department of Physics, Binghamton University, Binghamton, New York 13902-6000, USA
| | - E-A Kim
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - A P Mackenzie
- School of Physics and Astronomy, University of St Andrews, Fife KY16 9SS, UK.,Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - K Fujita
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Jinho Lee
- Institute of Applied Physics, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, South Korea.,Center for Correlated Electron Systems, Institute of Basic Science, Seoul 151-742, South Korea
| | - J C Séamus Davis
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.,School of Physics and Astronomy, University of St Andrews, Fife KY16 9SS, UK.,Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA
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44
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Fanfarillo L, Mori M, Campetella M, Grilli M, Caprara S. Glue function of optimally and overdoped cuprates from inversion of the Raman spectra. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:065701. [PMID: 26790363 DOI: 10.1088/0953-8984/28/6/065701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We address the issue of identifying the mediators of effective interactions in cuprates superconductors. Specifically, we use inversion theory to analyze Raman spectra of optimally and over-doped La2-x Sr x CuO4 samples. This allows us to extract the so-called glue function without making any a priori assumption based on any specific model. We use instead two different techniques, namely the singular value decomposition and a multi-rectangle decomposition. With both techniques we find consistent results showing that: (i) two distinct excitations are responsible for the glue function, which have completely different doping dependence. One excitation becomes weak above optimal doping, where on the contrary the other keeps (or even slightly increases) its strength; (ii) there is a marked temperature dependence on the weight and spectral distribution of these excitations, which therefore must have a somewhat critical character. It is quite natural to identify and characterize these two distinct excitations as damped antiferromagnetic spin waves and damped charge density waves, respectively. This sets the stage for a scenario in which superconductivity is concomitant and competing with a charge ordering instability.
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Affiliation(s)
- L Fanfarillo
- Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, Cantoblanco, E-28049 Madrid, Spain
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45
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Hansmann P, Ayral T, Tejeda A, Biermann S. Uncertainty principle for experimental measurements: Fast versus slow probes. Sci Rep 2016; 6:19728. [PMID: 26829902 PMCID: PMC4735290 DOI: 10.1038/srep19728] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/17/2015] [Indexed: 11/10/2022] Open
Abstract
The result of a physical measurement depends on the time scale of the experimental probe. In solid-state systems, this simple quantum mechanical principle has far-reaching consequences: the interplay of several degrees of freedom close to charge, spin or orbital instabilities combined with the disparity of the time scales associated to their fluctuations can lead to seemingly contradictory experimental findings. A particularly striking example is provided by systems of adatoms adsorbed on semiconductor surfaces where different experiments--angle-resolved photoemission, scanning tunneling microscopy and core-level spectroscopy--suggest different ordering phenomena. Using most recent first principles many-body techniques, we resolve this puzzle by invoking the time scales of fluctuations when approaching the different instabilities. These findings suggest a re-interpretation of ordering phenomena and their fluctuations in a wide class of solid-state systems ranging from organic materials to high-temperature superconducting cuprates.
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Affiliation(s)
- P Hansmann
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Univ. Paris-Saclay, 91128 Palaiseau, France.,Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - T Ayral
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Univ. Paris-Saclay, 91128 Palaiseau, France.,Institut de Physique Théorique (IPhT), CEA, CNRS, URA 2306, 91191 Gif-sur-Yvette, France
| | - A Tejeda
- Laboratoire de Physique des Solides, CNRS, Univ. Paris Sud, Univ. Paris-Saclay, 91405 Orsay, France
| | - S Biermann
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Univ. Paris-Saclay, 91128 Palaiseau, France.,Collège de France, 11 place Marcelin Berthelot, 75005 Paris, France.,European Theoretical Synchrotron Facility, Europe
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46
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Markiewicz RS, Lorenzana J, Seibold G, Bansil A. Short range smectic order driving long range nematic order: example of cuprates. Sci Rep 2016; 6:19678. [PMID: 26813579 PMCID: PMC4728556 DOI: 10.1038/srep19678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 11/19/2015] [Indexed: 12/03/2022] Open
Abstract
We present a model for describing the combined presence of nematic and 'smectic' or stripe-like orders seen in recent scanning tunneling microscopy (STM) experiments on cuprates. The smectic order is treated as an electronic charge density wave with an associated Peierls distortion or a 'Pomeranchuk wave'. This primary order is restricted to nanoscale domains by disorder effects, while the secondary coupling to strain generates the nematic order with a considerably longer range. A variety of experimental results are shown to be consistent with our theoretical predictions.
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Affiliation(s)
- R. S. Markiewicz
- Physics Department, Northeastern University, Boston MA 02115, USA
| | - J. Lorenzana
- ISC-CNR and Dipartimento di Fisica, Università di Roma “La Sapienza”, P. Aldo Moro 2, 00185 Roma, Italy
- ISC-CNR, Via dei Taurini 19, I-00185 Roma, Italy
| | - G. Seibold
- Institut Für Physik, BTU Cottbus-Senftenberg, PBox 101344, 03013 Cottbus, Germany
| | - A. Bansil
- Physics Department, Northeastern University, Boston MA 02115, USA
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47
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Tu WL, Lee TK. Genesis of charge orders in high temperature superconductors. Sci Rep 2016; 6:18675. [PMID: 26732076 PMCID: PMC4702086 DOI: 10.1038/srep18675] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 11/23/2015] [Indexed: 11/10/2022] Open
Abstract
One of the most puzzling facts about cuprate high-temperature superconductors in the lightly doped regime is the coexistence of uniform superconductivity and/or antiferromagnetism with many low-energy charge-ordered states in a unidirectional charge density wave or a bidirectional checkerboard structure. Recent experiments have discovered that these charge density waves exhibit different symmetries in their intra-unit-cell form factors for different cuprate families. Using a renormalized mean-field theory for a well-known, strongly correlated model of cuprates, we obtain a number of charge-ordered states with nearly degenerate energies without invoking special features of the Fermi surface. All of these self-consistent solutions have a pair density wave intertwined with a charge density wave and sometimes a spin density wave. Most of these states vanish in the underdoped regime, except for one with a large d-form factor that vanishes at approximately 19% doping of the holes, as reported by experiments. Furthermore, these states could be modified to have a global superconducting order, with a nodal-like density of states at low energy.
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Affiliation(s)
- Wei-Lin Tu
- Department of Physics, National Taiwan University, Daan Taipei 10617, Taiwan
- Institute of Physics, Academia Sinica, Nankang Taipei 11529, Taiwan
| | - Ting-Kuo Lee
- Institute of Physics, Academia Sinica, Nankang Taipei 11529, Taiwan
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48
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The microscopic structure of charge density waves in underdoped YBa2Cu3O6.54 revealed by X-ray diffraction. Nat Commun 2015; 6:10064. [PMID: 26648114 PMCID: PMC4682044 DOI: 10.1038/ncomms10064] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 10/30/2015] [Indexed: 11/09/2022] Open
Abstract
Charge density wave (CDW) order appears throughout the underdoped high-temperature cuprate superconductors, but the underlying symmetry breaking and the origin of the CDW remain unclear. We use X-ray diffraction to determine the microscopic structure of the CDWs in an archetypical cuprate YBa2Cu3O6.54 at its superconducting transition temperature ∼60 K. We find that the CDWs in this material break the mirror symmetry of the CuO2 bilayers. The ionic displacements in the CDWs have two components, which are perpendicular and parallel to the CuO2 planes, and are out of phase with each other. The planar oxygen atoms have the largest displacements, perpendicular to the CuO2 planes. Our results allow many electronic properties of the underdoped cuprates to be understood. For instance, the CDWs will lead to local variations in the electronic structure, giving an explicit explanation of density-wave states with broken symmetry observed in scanning tunnelling microscopy and soft X-ray measurements. Near to the superconducting state, cuprates display spatially-periodic charge density variations. Here, the authors use x-ray diffraction to determine the microscopic structure, showing how charge density waves in underdoped YBa2Cu3O6.54 break the symmetry of the superconducting layers.
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49
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Yamamoto A, Takeshita N, Terakura C, Tokura Y. High pressure effects revisited for the cuprate superconductor family with highest critical temperature. Nat Commun 2015; 6:8990. [PMID: 26619829 PMCID: PMC4686855 DOI: 10.1038/ncomms9990] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 10/22/2015] [Indexed: 11/13/2022] Open
Abstract
How to enhance the superconducting critical temperature (Tc) has been a primary issue since the discovery of superconductivity. The highest Tc reported so far is 166 K in HgBa2Ca2Cu3O8+δ (Hg1223) at high pressure of 23 GPa, as determined with the reduction onset, but not zero, of resistivity. To clarify the possible condition of the real maximum Tc, it is worth revisiting the effects of pressure on Tc in the highest Tc family. Here we report a systematic study of the pressure dependence of Tc in HgBa2CaCu2O6+δ (Hg1212) and Hg1223 with the doping level from underdoped to overdoped. The Tc with zero resistivity is probed with a cubic-anvil-type apparatus that can produce hydrostatic pressures. Variation, not only increase but also decrease, of Tc in Hg1212 and Hg1223 with pressure strongly depends on the initial doping levels. In particular, we confirm a maximum Tc of 153 K at 22 GPa in slightly underdoped Hg1223. Superconductivity, zero-resistance electrical transport, exists up to temperatures above 150 K in mercury-based cuprates under pressure. Here, the authors revisit the pressure dependence of the superconducting transition temperature in these materials and find a strong dependence on initial doping.
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Affiliation(s)
- Ayako Yamamoto
- Strong Correlation Physics Division, RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
| | - Nao Takeshita
- Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8568, Japan
| | - Chieko Terakura
- Strong Correlation Physics Division, RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
| | - Yoshinori Tokura
- Strong Correlation Physics Division, RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan.,Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
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Baireuther P, Hyart T, Tarasinski B, Beenakker CWJ. Andreev-Bragg Reflection from an Amperian Superconductor. PHYSICAL REVIEW LETTERS 2015; 115:097001. [PMID: 26371674 DOI: 10.1103/physrevlett.115.097001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Indexed: 06/05/2023]
Abstract
We show how an electrical measurement can detect the pairing of electrons on the same side of the Fermi surface (Amperian pairing), recently proposed by Patrick Lee for the pseudogap phase of high-Tc cuprate superconductors. Bragg scattering from the pair-density wave introduces odd multiples of 2k(F) momentum shifts when an electron incident from a normal metal is Andreev reflected as a hole. These Andreev-Bragg reflections can be detected in a three-terminal device, containing a ballistic Y junction between normal leads (1, 2) and the superconductor. The cross-conductance dI1/dV2 has the opposite sign for Amperian pairing than it has either in the normal state or for the usual BCS pairing.
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Affiliation(s)
- P Baireuther
- Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands
| | - T Hyart
- Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands
| | - B Tarasinski
- Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands
| | - C W J Beenakker
- Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands
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