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Wang Z, Pei K, Yang L, Yang C, Chen G, Zhao X, Wang C, Liu Z, Li Y, Che R, Zhu J. Topological spin texture in the pseudogap phase of a high-T c superconductor. Nature 2023; 615:405-410. [PMID: 36813970 DOI: 10.1038/s41586-023-05731-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 01/13/2023] [Indexed: 02/24/2023]
Abstract
An outstanding challenge in condensed-matter-physics research over the past three decades has been to understand the pseudogap (PG) phenomenon of the high-transition-temperature (high-Tc) copper oxides. A variety of experiments have indicated a symmetry-broken state below the characteristic temperature T* (refs. 1-8). Among them, although the optical study5 indicated the mesoscopic domains to be small, all these experiments lack nanometre-scale spatial resolution, and the microscopic order parameter has so far remained elusive. Here we report, to our knowledge, the first direct observation of topological spin texture in an underdoped cuprate, YBa2Cu3O6.5, in the PG state, using Lorentz transmission electron microscopy (LTEM). The spin texture features vortex-like magnetization density in the CuO2 sheets, with a relatively large length scale of about 100 nm. We identify the phase-diagram region in which the topological spin texture exists and demonstrate the ortho-II oxygen order and suitable sample thickness to be crucial for its observation by our technique. We also discuss an intriguing interplay observed among the topological spin texture, PG state, charge order and superconductivity.
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Affiliation(s)
- Zechao Wang
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, People's Republic of China
- Ji Hua Laboratory, Foshan, People's Republic of China
| | - Ke Pei
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Liting Yang
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Chendi Yang
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Guanyu Chen
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Xuebing Zhao
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
- Zhejiang Laboratory, Hangzhou, People's Republic of China
| | - Chao Wang
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
- Zhejiang Laboratory, Hangzhou, People's Republic of China
| | - Zhengwang Liu
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Yuan Li
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, People's Republic of China.
- Collaborative Innovation Center of Quantum Matter, Beijing, People's Republic of China.
| | - Renchao Che
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China.
| | - Jing Zhu
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, People's Republic of China.
- Ji Hua Laboratory, Foshan, People's Republic of China.
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2
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Persky E, Bjørlig AV, Feldman I, Almoalem A, Altman E, Berg E, Kimchi I, Ruhman J, Kanigel A, Kalisky B. Magnetic memory and spontaneous vortices in a van der Waals superconductor. Nature 2022; 607:692-696. [PMID: 35896649 DOI: 10.1038/s41586-022-04855-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 05/11/2022] [Indexed: 11/09/2022]
Abstract
Doped Mott insulators exhibit some of the most intriguing quantum phases of matter, including quantum spin liquids, unconventional superconductors and non-Fermi liquid metals1-3. Such phases often arise when itinerant electrons are close to a Mott insulating state, and thus experience strong spatial correlations. Proximity between different layers of van der Waals heterostructures naturally realizes a platform for experimentally studying the relationship between localized, correlated electrons and itinerant electrons. Here we explore this relationship by studying the magnetic landscape of tantalum disulfide 4Hb-TaS2, which realizes an alternating stacking of a candidate spin liquid and a superconductor4. We report on a spontaneous vortex phase whose vortex density can be trained in the normal state. We show that time-reversal symmetry is broken in the normal state, indicating the presence of a magnetic phase independent of the superconductor. Notably, this phase does not generate ferromagnetic signals that are detectable using conventional techniques. We use scanning superconducting quantum interference device microscopy to show that it is incompatible with ferromagnetic ordering. The discovery of this unusual magnetic phase illustrates how combining superconductivity with a strongly correlated system can lead to unexpected physics.
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Affiliation(s)
- Eylon Persky
- Department of Physics, Bar Ilan University, Ramat Gan, Israel. .,Bar Ilan Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, Israel.
| | - Anders V Bjørlig
- Department of Physics, Bar Ilan University, Ramat Gan, Israel.,Bar Ilan Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, Israel
| | - Irena Feldman
- Department of Physics, Technion-Israel Institute of Technology, Haifa, Israel
| | - Avior Almoalem
- Department of Physics, Technion-Israel Institute of Technology, Haifa, Israel
| | - Ehud Altman
- Department of Physics, University of California, Berkeley, Berkeley, CA, USA.,Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Erez Berg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Itamar Kimchi
- School of Physics, Georgia Institute of Technology, Atlanta, GA, USA
| | - Jonathan Ruhman
- Department of Physics, Bar Ilan University, Ramat Gan, Israel
| | - Amit Kanigel
- Department of Physics, Technion-Israel Institute of Technology, Haifa, Israel
| | - Beena Kalisky
- Department of Physics, Bar Ilan University, Ramat Gan, Israel. .,Bar Ilan Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, Israel.
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3
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Zhang J, Ding Z, Tan C, Huang K, Bernal OO, Ho PC, Morris GD, Hillier AD, Biswas PK, Cottrell SP, Xiang H, Yao X, MacLaughlin DE, Shu L. Discovery of slow magnetic fluctuations and critical slowing down in the pseudogap phase of YBa 2Cu 3O y. SCIENCE ADVANCES 2018; 4:eaao5235. [PMID: 29326982 PMCID: PMC5756666 DOI: 10.1126/sciadv.aao5235] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/30/2017] [Indexed: 05/30/2023]
Abstract
The origin of the pseudogap region below a temperature T* is at the heart of the mysteries of cuprate high-temperature superconductors. Unusual properties of the pseudogap phase, such as broken time-reversal and inversion symmetry are observed in several symmetry-sensitive experiments: polarized neutron diffraction, optical birefringence, dichroic angle-resolved photoemission spectroscopy, second harmonic generation, and polar Kerr effect. These properties suggest that the pseudogap region is a genuine thermodynamic phase and are predicted by theories invoking ordered loop currents or other forms of intra-unit-cell (IUC) magnetic order. However, muon spin rotation (μSR) and nuclear magnetic resonance (NMR) experiments do not see the static local fields expected for magnetic order, leaving room for skepticism. The magnetic resonance probes have much longer time scales, however, over which local fields could be averaged by fluctuations. The observable effect of the fluctuations in magnetic resonance is then dynamic relaxation. We have measured dynamic muon spin relaxation rates in single crystals of YBa2Cu3O y (6.72 < y < 6.95) and have discovered "slow" fluctuating magnetic fields with magnitudes and fluctuation rates of the expected orders of magnitude that set in consistently at temperatures Tmag ≈ T*. The absence of any static field (to which μSR would be linearly sensitive) is consistent with the finite correlation length from neutron diffraction. Equally important, these fluctuations exhibit the critical slowing down at Tmag expected near a time-reversal symmetry breaking transition. Our results explain the absence of static magnetism and provide support for the existence of IUC magnetic order in the pseudogap phase.
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Affiliation(s)
- Jian Zhang
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People’s Republic of China
| | - Zhaofeng Ding
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People’s Republic of China
| | - Cheng Tan
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People’s Republic of China
| | - Kevin Huang
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People’s Republic of China
| | - Oscar O. Bernal
- Department of Physics and Astronomy, California State University, Los Angeles, CA 90032, USA
| | - Pei-Chun Ho
- Department of Physics, California State University, Fresno, CA 93740, USA
| | | | - Adrian D. Hillier
- ISIS Facility, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0QX, UK
| | - Pabitra K. Biswas
- ISIS Facility, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0QX, UK
| | - Stephen P. Cottrell
- ISIS Facility, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0QX, UK
| | - Hui Xiang
- State Key Lab for Metal Matrix Composites, Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Xin Yao
- State Key Lab for Metal Matrix Composites, Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, People’s Republic of China
| | - Douglas E. MacLaughlin
- Department of Physics and Astronomy, University of California, Riverside, Riverside, CA 92521, USA
| | - Lei Shu
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People’s Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, People’s Republic of China
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4
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Scanderbeg DJ, Taylor BJ, Baumbach RE, Paglione J, Maple MB. Electrical and thermal transport properties of the electron-doped cuprate Sm 2-x Ce x CuO 4-y system. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:485702. [PMID: 27705951 DOI: 10.1088/0953-8984/28/48/485702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Electrical and thermal transport measurements were performed on thin films of the electron-doped superconductor Sm2-x Ce x CuO4-y (x = 0.13 - 0.19) in order to study the evolving nature of the charge carriers from the under-doped to over-doped regime. A temperature versus cerium content (T - x) phase diagram has been constructed from the electrical transport measurements, yielding a superconducting region similar to that found for other electron-doped superconductors. Thermopower measurements show a dramatic change from the underdoped region (x < 0.15) to the overdoped region (x > 0.15). Application of the Fisher-Fisher-Huse (FFH) vortex glass scaling model to the magnetoresistance data was found to be insufficient to describe the data in the region of the vortex-solid to vortex-liquid transition. It was found instead that the modified vortex glass scaling model of Rydh, Rapp, and Anderson provided a good description of the data, indicating the importance of the applied field on the pinning landscape. A magnetic field versus temperature (H - T) phase diagram has also been constructed for the films with [Formula: see text], displaying the evolution of the vortex glass melting lines H g (T) across the superconducting regime.
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5
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Sebastian SE, Harrison N, Lonzarich GG. Quantum oscillations in the high-Tc cuprates. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2011; 369:1687-1711. [PMID: 21422021 DOI: 10.1098/rsta.2010.0243] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We review recent progress in the study of quantum oscillations as a tool for uniquely probing low-energy electronic excitations in high-T(c) cuprate superconductors. Quantum oscillations in the underdoped cuprates reveal that a close correspondence with Landau Fermi-liquid behaviour persists in the accessed regions of the phase diagram, where small pockets are observed. Quantum oscillation results are viewed in the context of momentum-resolved probes such as photoemission, and evidence examined from complementary experiments for potential explanations for the transformation from a large Fermi surface into small sections. Indications from quantum oscillation measurements of a low-energy Fermi surface instability at low dopings under the superconducting dome at the metal-insulator transition are reviewed, and potential implications for enhanced superconducting temperatures are discussed.
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Affiliation(s)
- Suchitra E Sebastian
- Department of Physics, Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, UK.
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6
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Sonier JE, Pacradouni V, Sabok-Sayr SA, Hardy WN, Bonn DA, Liang R, Mook HA. Detection of the unusual magnetic orders in the pseudogap region of a high-temperature superconducting YBa2Cu3O6.6 crystal by muon-spin relaxation. PHYSICAL REVIEW LETTERS 2009; 103:167002. [PMID: 19905717 DOI: 10.1103/physrevlett.103.167002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Indexed: 05/28/2023]
Abstract
We present muon-spin relaxation (muSR) measurements on a large YBa2Cu3O6.6 single crystal in which two kinds of unusual magnetic order have been detected in the pseudogap region by neutron scattering. A comparison is made to measurements on smaller, higher quality YBa2Cu3Oy single crystals. One type of magnetic order is observed in all samples, but does not evolve significantly with hole doping. A second type of unusual magnetic order is observed only in the YBa2Cu3O6.6 single crystal. This magnetism has an ordered magnetic moment that is quantitatively consistent with the neutron experiments, but is confined to just a small volume of the sample ( approximately 3%). Our findings do not support theories that ascribe the pseudogap to a state characterized by loop-current order, but instead indicate that dilute impurity phases are the source of the unusual magnetic orders in YBa2Cu3Oy.
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Affiliation(s)
- J E Sonier
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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7
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Shekhter A, Shu L, Aji V, MacLaughlin DE, Varma CM. Screening of point charge impurities in highly anisotropic metals: application to mu+-spin relaxation in underdoped cuprate superconductors. PHYSICAL REVIEW LETTERS 2008; 101:227004. [PMID: 19113515 DOI: 10.1103/physrevlett.101.227004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Indexed: 05/27/2023]
Abstract
We calculate the screening charge density distribution due to a point charge, such as that of a positive muon (mu+), placed between the planes of a highly anisotropic layered metal. In underdoped hole cuprates the screening charge converts the charge density in the metallic-plane unit cells in the vicinity of the mu+ to nearly its value in the insulating state. The current-loop-ordered state observed by polarized neutron diffraction then vanishes in such cells, and also in nearby cells over a distance of order the intrinsic correlation length of the loop-ordered state. This strongly suppresses the magnetic field at the mu+ site. We estimate this suppressed field in underdoped YBa2Cu3O6+x and La2-xSrxCuO4, and find consistency with the observed approximately 0.2 G field in the former case and the observed upper bound of approximately 0.2 G in the latter case. This resolves the controversy between the neutron diffraction and mu-spin relaxation experiments.
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Affiliation(s)
- Arkady Shekhter
- Department of Physics and Astronomy, University of California, Riverside, California 92521, USA
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8
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Unusual magnetic order in the pseudogap region of the superconductor HgBa2CuO4+delta. Nature 2008; 455:372-5. [PMID: 18800135 DOI: 10.1038/nature07251] [Citation(s) in RCA: 247] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 07/02/2008] [Indexed: 11/08/2022]
Abstract
The pseudogap region of the phase diagram is an important unsolved puzzle in the field of high-transition-temperature (high-T(c)) superconductivity, characterized by anomalous physical properties. There are open questions about the number of distinct phases and the possible presence of a quantum-critical point underneath the superconducting dome. The picture has remained unclear because there has not been conclusive evidence for a new type of order. Neutron scattering measurements for YBa(2)Cu(3)O(6+delta) (YBCO) resulted in contradictory claims of no and weak magnetic order, and the interpretation of muon spin relaxation measurements on YBCO and of circularly polarized photoemission experiments on Bi(2)Sr(2)CaCu(2)O(8+delta)(refs 12, 13) has been controversial. Here we use polarized neutron diffraction to demonstrate for the model superconductor HgBa(2)CuO(4+delta) (Hg1201) that the characteristic temperature T* marks the onset of an unusual magnetic order. Together with recent results for YBCO, this observation constitutes a demonstration of the universal existence of such a state. The findings appear to rule out theories that regard T* as a crossover temperature rather than a phase transition temperature. Instead, they are consistent with a variant of previously proposed charge-current-loop order that involves apical oxygen orbitals, and with the notion that many of the unusual properties arise from the presence of a quantum-critical point.
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9
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Sonier JE, Ilton M, Pacradouni V, Kaiser CV, Sabok-Sayr SA, Ando Y, Komiya S, Hardy WN, Bonn DA, Liang R, Atkinson WA. Inhomogeneous magnetic-field response of YBa2Cu3Oy and La2-xSrxCuO4 persisting above the bulk superconducting transition temperature. PHYSICAL REVIEW LETTERS 2008; 101:117001. [PMID: 18851316 DOI: 10.1103/physrevlett.101.117001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2008] [Indexed: 05/26/2023]
Abstract
We report that in YBa2Cu3Oy and La2-xSrxCuO4 there is a spatially inhomogeneous response to the magnetic field for temperatures T extending well above the bulk-superconducting transition temperature Tc. An inhomogeneous magnetic response is observed above Tc even in ortho-II YBa2Cu3O6.50, which has highly ordered doping. The degree of the field inhomogeneity above Tc tracks the hole-doping dependences of both Tc and the density of the superconducting carriers below Tc, and therefore is apparently coupled to superconductivity.
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Affiliation(s)
- J E Sonier
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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10
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MacDougall GJ, Aczel AA, Carlo JP, Ito T, Rodriguez J, Russo PL, Uemura YJ, Wakimoto S, Luke GM. Absence of broken time-reversal symmetry in the pseudogap state of the high temperature La(2-x)SrxCuO4 superconductor from muon-spin-relaxation measurements. PHYSICAL REVIEW LETTERS 2008; 101:017001. [PMID: 18764143 DOI: 10.1103/physrevlett.101.017001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Indexed: 05/26/2023]
Abstract
We have performed zero-field muon-spin-relaxation measurements on single crystals of La(2-x)SrxCuO4 to search for spontaneous currents in the pseudogap state. By comparing measurements on materials across the phase diagram, we put strict upper limits on any possible time-reversal symmetry breaking fields that could be associated with the pseudogap. Comparison between experimental limits and the proposed circulating current states effectively eliminates the possibility that such states exist in this family of materials.
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Affiliation(s)
- G J MacDougall
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada, L8S-4M1
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11
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Tewari S, Zhang C, Yakovenko VM, Das Sarma S. Time-reversal symmetry breaking by a (d+id) density-wave state in underdoped cuprate superconductors. PHYSICAL REVIEW LETTERS 2008; 100:217004. [PMID: 18518628 DOI: 10.1103/physrevlett.100.217004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Indexed: 05/26/2023]
Abstract
It was proposed that the id(x(2)-y(2)) density-wave state (DDW) may be responsible for the pseudogap behavior in the underdoped cuprates. Here we show that the admixture of a small d(xy) component to the DDW state breaks the symmetry between the counterpropagating orbital currents of the DDW state and, thus, violates the macroscopic time-reversal symmetry. This symmetry breaking results in a nonzero polar Kerr effect, which has recently been observed in the pseudogap phase.
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Affiliation(s)
- Sumanta Tewari
- Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA
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12
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Xia J, Schemm E, Deutscher G, Kivelson SA, Bonn DA, Hardy WN, Liang R, Siemons W, Koster G, Fejer MM, Kapitulnik A. Polar Kerr-effect measurements of the high-temperature YBa2Cu3O6+x superconductor: evidence for broken symmetry near the pseudogap temperature. PHYSICAL REVIEW LETTERS 2008; 100:127002. [PMID: 18517903 DOI: 10.1103/physrevlett.100.127002] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Indexed: 05/26/2023]
Abstract
The polar Kerr effect in the high-T_(c) superconductor YBa2Cu3O6+x was measured at zero magnetic field with high precision using a cyogenic Sagnac fiber interferometer. We observed nonzero Kerr rotations of order approximately 1 microrad appearing near the pseudogap temperature T(*) and marking what appears to be a true phase transition. Anomalous magnetic behavior in magnetic-field training of the effect suggests that time reversal symmetry is already broken above room temperature.
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Affiliation(s)
- Jing Xia
- Department of Physics, Stanford University, Stanford, California 94305, USA
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13
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Wilson JA. Structural matters in HTSC: the origin and form of stripe organization and checkerboarding. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2006; 18:R69-R99. [PMID: 21697557 DOI: 10.1088/0953-8984/18/6/r02] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The paper deals with the controversial charge and spin self-organization phenomena in the HTSC cuprates, of which neutron, x-ray, STM and ARPES experiments give complementary, sometimes apparently contradictory glimpses. The examination has been set in the context of the boson-fermion, negative-U understanding of HTSC advocated over many years by the author. Stripe models are developed which are 2-q in nature and diagonal in form. For such a geometry to be compatible with the data rests upon both the spin and charge arrays being face-centred. Various special doping concentrations are closely looked at, in particular p = 0.1836 or 9/49, which is associated with the maximization of the superconducting condensation energy and the termination of the pseudogap regime. The stripe models are dictated by real space organization of the holes, whereas the dispersionless checkerboarding is interpreted in terms of correlation driven collapse of normal Fermi surface behaviour and response functions. The incommensurate spin diffraction below the 'resonance energy' is seen as in no way expressing spin-wave physics or Fermi surface nesting, but is driven by charge and strain (Jahn-Teller) considerations, and it stands virtually without dispersion. The apparent dispersion comes from the downward dispersion of the resonance peak, and the growth of a further incoherent commensurate peak pursuant upon the falling level of charge stripe organization under excitation.
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Affiliation(s)
- John A Wilson
- H H Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL, UK
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14
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15
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Blundell SJ. Muon-Spin Rotation Studies of Electronic Properties of Molecular Conductors and Superconductors. Chem Rev 2004; 104:5717-36. [PMID: 15535666 DOI: 10.1021/cr030632e] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stephen J Blundell
- Department of Physics, Oxford University, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.
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16
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Miller RI, Kiefl RF, Brewer JH, Sonier JE, Chakhalian J, Dunsiger S, Morris GD, Price AN, Bonn DA, Hardy WH, Liang R. Evidence for static magnetism in the vortex cores of ortho-II YBa2Cu3O6.50. PHYSICAL REVIEW LETTERS 2002; 88:137002. [PMID: 11955116 DOI: 10.1103/physrevlett.88.137002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2001] [Indexed: 05/23/2023]
Abstract
Evidence for static alternating magnetic fields in the vortex cores of underdoped YBa2Cu3O6+x is reported. Muon spin rotation measurements of the internal magnetic field distribution of the vortex state of YBa2Cu3O6.50 in applied fields of H = 1 T and H = 4 T reveal a feature in the high-field tail of the field distribution which is not present in optimally doped YBa2Cu3O6.95 and which fits well to a model with static magnetic fields in the vortex cores. The magnitude of the fields is estimated to be 18(2) G and decreases above T = 10 K. We discuss possible origins of the additional vortex core magnetism within the context of existing theories.
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Affiliation(s)
- R I Miller
- Department of Physics & Astronomy, University of British Columbia, Vancouver, Canada.
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17
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Eremin M, Rigamonti A. Spin-freezing mechanism in underdoped superconducting cuprates. PHYSICAL REVIEW LETTERS 2002; 88:037002. [PMID: 11801082 DOI: 10.1103/physrevlett.88.037002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2001] [Indexed: 05/23/2023]
Abstract
The spin-freezing process in underdoped cuprate superconductors, observed most by NMR-NQR relaxation and muon spin rotation and sometimes interpreted as coexistence of antiferromagnetic and superconducting states, is generally thought to result from randomly distributed magnetic moments related to charge inhomogeneities (possibly stripes) which exhibit slowing down of their fluctuations on cooling below T(c). Instead, we describe the experimental findings as due to fluctuating magnetic fields caused by sliding motions of orbital currents coexisting with d-wave superconducting state. A direct explanation of the experimental results, in underdoped Y2-xCaxBa2Cu3O6.1 and La2-xSrxCuO4, is thus given in terms of freezing of orbital current fluctuations, and mean squared amplitudes of the related internal magnetic fields are estimated.
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Affiliation(s)
- M Eremin
- Department of Physics "A. Volta," University of Pavia and Unita' INFM, Via Bassi 6, I-7100 Pavia, Italy
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