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Wang S, Kennedy N, Fujita K, Uchida SI, Eisaki H, Johnson PD, Davis JCS, O'Mahony SM. Discovery of orbital ordering in Bi 2Sr 2CaCu 2O 8+x. NATURE MATERIALS 2024; 23:492-498. [PMID: 38438620 PMCID: PMC10990940 DOI: 10.1038/s41563-024-01817-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 01/22/2024] [Indexed: 03/06/2024]
Abstract
The primordial ingredient of cuprate superconductivity is the CuO2 unit cell. Theories usually concentrate on the intra-atom Coulombic interactions dominating the 3d9 and 3d10 configurations of each copper ion. However, if Coulombic interactions also occur between electrons of the 2p6 orbitals of each planar oxygen atom, spontaneous orbital ordering may split their energy levels. This long-predicted intra-unit-cell symmetry breaking should generate an orbitally ordered phase, for which the charge transfer energy ε separating the 2p6 and 3d10 orbitals is distinct for the two oxygen atoms. Here we introduce sublattice-resolved ε(r) imaging to CuO2 studies and discover intra-unit-cell rotational symmetry breaking of ε(r). Spatially, this state is arranged in disordered Ising domains of orthogonally oriented orbital order bounded by dopant ions, and within whose domain walls low-energy electronic quadrupolar two-level systems occur. Overall, these data reveal a Q = 0 orbitally ordered state that splits the oxygen energy levels by ~50 meV, in underdoped CuO2.
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Affiliation(s)
- Shuqiu Wang
- Clarendon Laboratory, University of Oxford, Oxford, UK.
- Department of Physics, Cornell University, Ithaca, NY, USA.
- H. H. Wills Physics Laboratory, University of Bristol, Bristol, UK.
| | - Niall Kennedy
- Clarendon Laboratory, University of Oxford, Oxford, UK
- School of Physics, University College Cork, Cork, Ireland
| | - Kazuhiro Fujita
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | | | - Hiroshi Eisaki
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Peter D Johnson
- Clarendon Laboratory, University of Oxford, Oxford, UK
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - J C Séamus Davis
- Clarendon Laboratory, University of Oxford, Oxford, UK.
- Department of Physics, Cornell University, Ithaca, NY, USA.
- School of Physics, University College Cork, Cork, Ireland.
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.
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2
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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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3
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Shragai A, Theuss F, Grissonnanche G, Ramshaw BJ. Rapid method for computing the mechanical resonances of irregular objects. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:119. [PMID: 36732270 DOI: 10.1121/10.0016813] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 12/13/2022] [Indexed: 06/18/2023]
Abstract
A solid object's geometry, density, and elastic moduli completely determine its spectrum of normal modes. Solving the inverse problem-determining a material's elastic moduli given a set of resonance frequencies and sample geometry-relies on the ability to compute resonance spectra accurately and efficiently. Established methods for calculating these spectra are either fast but limited to simple geometries, or are applicable to arbitrarily shaped samples at the cost of being prohibitively slow. Here, we describe a method to rapidly compute the normal modes of irregularly shaped objects using entirely open-source software. Our method's accuracy compares favorably with existing methods for simple geometries and shows a significant improvement in speed over existing methods for irregular geometries.
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Affiliation(s)
- Avi Shragai
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - Florian Theuss
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - Gaël Grissonnanche
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - B J Ramshaw
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
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4
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High-harmonic spectroscopy of quantum phase transitions in a high-Tc superconductor. Proc Natl Acad Sci U S A 2022; 119:e2207766119. [PMID: 36161921 PMCID: PMC9546568 DOI: 10.1073/pnas.2207766119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report on the nonlinear optical signatures of quantum phase transitions in the high-temperature superconductor YBCO, observed through high harmonic generation. While the linear optical response of the material is largely unchanged when cooling across the phase transitions, the nonlinear optical response sensitively imprints two critical points, one at the critical temperature of the cuprate with the exponential growth of the surface harmonic yield in the superconducting phase and another critical point, which marks the transition from strange metal to pseudogap phase. To reveal the underlying microscopic quantum dynamics, a strong-field quasi-Hubbard model was developed, which describes the measured optical response dependent on the formation of Cooper pairs. Further, the theory provides insight into the carrier scattering dynamics and allows us to differentiate between the superconducting, pseudogap, and strange metal phases. The direct connection between nonlinear optical response and microscopic dynamics provides a powerful methodology to study quantum phase transitions in correlated materials. Further implications are light wave control over intricate quantum phases, light-matter hybrids, and application for optical quantum computing.
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5
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Fledgling Quantum Spin Hall Effect in Pseudo Gap Phase of Bi2212. Symmetry (Basel) 2022. [DOI: 10.3390/sym14081746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We studied the emergence of the quantum spin Hall (QSH) states for the pseudo-gap (PG) phase of Bi2212 bilayer system, assumed to be D-density wave (DDW) ordered, starting with a strong Rashba spin-orbit coupling (SOC) armed, and the time reversal symmetry (TRS) complaint Bloch Hamiltonian. The presence of strong SOC gives rise to non-trivial, spin-momentum locked spin texture tunable by electric field. The emergence of quantum anomalous Hall effect with TRS broken Chiral DDW Hamiltonian of Das Sarma et al. is found to be possible.
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Torres J, Flores-Betancourt A, Hermann RP. RUScal: Software for the analysis of resonant ultrasound spectroscopy measurements. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:3547. [PMID: 35649907 DOI: 10.1121/10.0011397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
Resonant ultrasound spectroscopy is used to nondestructively measure the elastic resonances of small solids to elucidate the material's elastic properties or other qualities like size, shape, or composition. Here, we introduce the software RUScal for the purpose of determining elastic properties by analyzing the eigenfrequencies of solid specimens with common shapes, such as rectangular parallelepipeds, cylinders (solid and hollow tube), ellipsoids, and octahedrons, as well as irregularly shaped ellipsoids that can be described analytically. All symmetry classes are supported, from isotropic to triclinic, along with the option to add or remove up to three orthogonal mirror planes as well as the ability to reorient the crystal axes with respect the sample edges via Euler angles. Additional features include tools to help find initial sets of elastic constants, including grid exploration and Monte Carlo methods, a tool to analyze frequencies as a function of sample length or crystal orientation, an error analysis tool to assess fit quality, and formatting of the input and output files for batch fitting, e.g., as a function of temperature. This software was validated with published resonant ultrasound spectroscopy data for various materials, shapes, and symmetries with noted improvements in calculation time compared to finite element methods.
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Affiliation(s)
- James Torres
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Alexis Flores-Betancourt
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Raphaël P Hermann
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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7
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Comparing Thickness and Doping-Induced Effects on the Normal States of Infinite-Layer Electron-Doped Cuprates: Is There Anything to Learn? NANOMATERIALS 2022; 12:nano12071092. [PMID: 35407212 PMCID: PMC9044742 DOI: 10.3390/nano12071092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 11/25/2022]
Abstract
We grew Sr1-xLaxCuO2 thin films and SrCuO2/Sr0.9La0.1CuO2/SrCuO2 trilayers by reflection high-energy diffraction-calibrated layer-by-layer molecular beam epitaxy, to study their electrical transport properties as a function of the doping and thickness of the central Sr0.9La0.1CuO2 layer. For the trilayer samples, as already observed in underdoped SLCO films, the electrical resistivity versus temperature curves as a function of the central layer thickness show, for thicknesses thinner than 20 unit cells, sudden upturns in the low temperature range with the possibility for identifying, in the normal state, the T* and a T** temperatures, respectively, separating high-temperature linear behavior and low-temperature quadratic dependence. By plotting the T* and T** values as a function of TConset for both the thin films and the trilayers, the data fall on the same curves. This result suggests that, for the investigated trilayers, the superconducting critical temperature is the important parameter able to describe the normal state properties and that, in the limit of very thin central layers, such properties are mainly influenced by the modification of the energy band structure and not by interface-related disorder.
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8
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Wang S, Choubey P, Chong YX, Chen W, Ren W, Eisaki H, Uchida S, Hirschfeld PJ, Davis JCS. Scattering interference signature of a pair density wave state in the cuprate pseudogap phase. Nat Commun 2021; 12:6087. [PMID: 34667154 PMCID: PMC8526682 DOI: 10.1038/s41467-021-26028-x] [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: 05/07/2021] [Accepted: 09/09/2021] [Indexed: 11/21/2022] Open
Abstract
An unidentified quantum fluid designated the pseudogap (PG) phase is produced by electron-density depletion in the CuO2 antiferromagnetic insulator. Current theories suggest that the PG phase may be a pair density wave (PDW) state characterized by a spatially modulating density of electron pairs. Such a state should exhibit a periodically modulating energy gap [Formula: see text] in real-space, and a characteristic quasiparticle scattering interference (QPI) signature [Formula: see text] in wavevector space. By studying strongly underdoped Bi2Sr2CaDyCu2O8 at hole-density ~0.08 in the superconductive phase, we detect the 8a0-periodic [Formula: see text] modulations signifying a PDW coexisting with superconductivity. Then, by visualizing the temperature dependence of this electronic structure from the superconducting into the pseudogap phase, we find the evolution of the scattering interference signature [Formula: see text] that is predicted specifically for the temperature dependence of an 8a0-periodic PDW. These observations are consistent with theory for the transition from a PDW state coexisting with d-wave superconductivity to a pure PDW state in the Bi2Sr2CaDyCu2O8 pseudogap phase.
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Affiliation(s)
- Shuqiu Wang
- Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Peayush Choubey
- Institut für Theoretische Physik III, Ruhr-Universität Bochum, Bochum, Germany
- Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, India
| | - Yi Xue Chong
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA
| | - Weijiong Chen
- Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Wangping Ren
- Clarendon Laboratory, University of Oxford, Oxford, UK
| | - H Eisaki
- Institute of Advanced Industrial Science and Tech., Tsukuba, Ibaraki, Japan
| | - S Uchida
- Institute of Advanced Industrial Science and Tech., Tsukuba, Ibaraki, Japan
| | | | - J C Séamus Davis
- Clarendon Laboratory, University of Oxford, Oxford, UK.
- LASSP, Department of Physics, Cornell University, Ithaca, NY, USA.
- Department of Physics, University College Cork, Cork, Ireland.
- Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany.
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9
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Tallon JL, Loram JW. Field-dependent specific heat of the canonical underdoped cuprate superconductor [Formula: see text]. Sci Rep 2020; 10:22288. [PMID: 33339851 PMCID: PMC7749183 DOI: 10.1038/s41598-020-79017-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/03/2020] [Indexed: 11/21/2022] Open
Abstract
The cuprate superconductor [Formula: see text], in comparison with most other cuprates, has a stable stoichiometry, is largely free of defects and may be regarded as the canonical underdoped cuprate, displaying marked pseudogap behaviour and an associated distinct weakening of superconducting properties. This cuprate 'pseudogap' manifests as a partial gap in the electronic density of states at the Fermi level and is observed in most spectroscopic properties. After several decades of intensive study it is widely believed that the pseudogap closes, mean-field like, near a characteristic temperature, [Formula: see text], which rises with decreasing hole concentration, p. Here, we report extensive field-dependent electronic specific heat studies on [Formula: see text] up to an unprecedented 400 K and show unequivocally that the pseudogap never closes, remaining open to at least 400 K where [Formula: see text] is typically presumed to be about 150 K. We show from the NMR Knight shift and the electronic entropy that the Wilson ratio is numerically consistent with a weakly-interacting Fermion system for the near-nodal states. And, from the field-dependent specific heat, we characterise the impact of fluctuations and impurity scattering on the thermodynamic properties.
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Affiliation(s)
- Jeffery L. Tallon
- Robinson Research Institute, and MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, P.O. Box 33436, Lower Hutt, 5046 New Zealand
| | - John W. Loram
- Cavendish Laboratory, Cambridge University, Cambridge, CB3 0HE UK
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10
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Nonadiabatic coupling of the dynamical structure to the superconductivity in YSr 2Cu 2.75Mo 0.25O 7.54 and Sr 2CuO 3.3. Proc Natl Acad Sci U S A 2020; 117:33099-33106. [PMID: 33318194 PMCID: PMC7776783 DOI: 10.1073/pnas.2018336117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The Cu extended X-ray absorption fine structure of YSr2Cu2.75Mo0.25O7.54 (with superconducting critical temperature, Tc, = 84 K) and Sr2CuO3.3 (Tc = 95 K) through their superconducting transitions demonstrates that the common factor in superconductivity in cuprates, including those prepared by high-pressure oxygenation, is an internal quantum tunneling polaron in its dynamical structure. In addition, Sr2CuO3.3 is the first material to show a concomitant transformation in this structure involving atom displacements >1 Å that would be expected to modify its Fermi surface, which would complicate the transition beyond a purely electronic one consisting of the pairing of electrons of opposite momentum across fixed electronic states. A crucial issue in cuprates is the extent and mechanism of the coupling of the lattice to the electrons and the superconductivity. Here we report Cu K edge extended X-ray absorption fine structure measurements elucidating the internal quantum tunneling polaron (iqtp) component of the dynamical structure in two heavily overdoped superconducting cuprate compounds, tetragonal YSr2Cu2.75Mo0.25O7.54 with superconducting critical temperature, Tc = 84 K and hole density p = 0.3 to 0.5 per planar Cu, and the tetragonal phase of Sr2CuO3.3 with Tc = 95 K and p = 0.6. In YSr2Cu2.75Mo0.25O7.54 changes in the Cu-apical O two-site distribution reflect a sequential renormalization of the double-well potential of this site beginning at Tc, with the energy difference between the two minima increasing by ∼6 meV between Tc and 52 K. Sr2CuO3.3 undergoes a radically larger transformation at Tc, >1-Å displacements of the apical O atoms. The principal feature of the dynamical structure underlying these transformations is the strongly anharmonic oscillation of the apical O atoms in a double-well potential that results in the observation of two distinct O sites whose Cu–O distances indicate different bonding modes and valence-charge distributions. The coupling of the superconductivity to the iqtp that originates in this nonadiabatic coupling between the electrons and lattice demonstrates an important role for the dynamical structure whereby pairing occurs even in a system where displacements of the atoms that are part of the transition are sufficiently large to alter the Fermi surface. The synchronization and dynamic coherence of the iqtps resulting from the strong interactions within a crystal would be expected to influence this process.
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Mydosh JA, Oppeneer PM, Riseborough PS. Hidden order and beyond: an experimental-theoretical overview of the multifaceted behavior of URu 2Si 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:143002. [PMID: 31801118 DOI: 10.1088/1361-648x/ab5eba] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This topical review describes the multitude of unconventional behaviors in the hidden order, heavy fermion, antiferromagnetic and superconducting phases of the intermetallic compound URu2Si2 when tuned with pressure, magnetic field, and substitutions for all three elements. Such 'perturbations' result in a variety of new phases beyond the mysterious hidden order that are only now being slowly understood through a series of state-of-the-science experimentation, along with an array of novel theoretical approaches. Despite all these efforts spanning more than 30 years, hidden order (HO) remains puzzling and non-clarified, and the search continues in 2019 into a fourth decade for its final resolution. Here we attempt to update the present situation of URu2Si2 importing the latest experimental results and theoretical proposals. First, let us consider the pristine compound as a function of temperature and report the recent measurements and models relating to its heavy Fermi liquid crossover, its HO and superconductivity (SC). Recent experiments and theories are surmized that address four-fold symmetry breaking (or nematicity), Isingness and unconventional excitation modes. Second, we review the pressure dependence of URu2Si2 and its transformation to antiferromagnetic long-range order. Next we confront the dramatic high magnetic-field phases requiring fields above 40 T. And finally, we attempt to answer how does random substitutions of other 5f elements for U, and 3d, 4d, and 5d elements for Ru, and even P for Si affect and transform the HO. Commensurately, recent theoretical models are summarized and then related to the intriguing experimental behavior.
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Affiliation(s)
- J A Mydosh
- Institute Lorentz and Kamerlingh Onnes Laboratory, Leiden University, NL-2300 RA Leiden, The Netherlands
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12
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Ghosh S, Matty M, Baumbach R, Bauer ED, Modic KA, Shekhter A, Mydosh JA, Kim EA, Ramshaw BJ. One-component order parameter in URu 2Si 2 uncovered by resonant ultrasound spectroscopy and machine learning. SCIENCE ADVANCES 2020; 6:eaaz4074. [PMID: 32181367 PMCID: PMC7060057 DOI: 10.1126/sciadv.aaz4074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
The unusual correlated state that emerges in URu2Si2 below T HO = 17.5 K is known as "hidden order" because even basic characteristics of the order parameter, such as its dimensionality (whether it has one component or two), are "hidden." We use resonant ultrasound spectroscopy to measure the symmetry-resolved elastic anomalies across T HO. We observe no anomalies in the shear elastic moduli, providing strong thermodynamic evidence for a one-component order parameter. We develop a machine learning framework that reaches this conclusion directly from the raw data, even in a crystal that is too small for traditional resonant ultrasound. Our result rules out a broad class of theories of hidden order based on two-component order parameters, and constrains the nature of the fluctuations from which unconventional superconductivity emerges at lower temperature. Our machine learning framework is a powerful new tool for classifying the ubiquitous competing orders in correlated electron systems.
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Affiliation(s)
- Sayak Ghosh
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA
| | - Michael Matty
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA
| | - Ryan Baumbach
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | - Eric D. Bauer
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - K. A. Modic
- Max Planck Institute for Chemical Physics of Solids, Dresden 01187, Germany
| | - Arkady Shekhter
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | - J. A. Mydosh
- Kamerlingh Onnes Laboratory and Institute Lorentz, Leiden University, 2300RA Leiden, Netherlands
| | - Eun-Ah Kim
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA
| | - B. J. Ramshaw
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA
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13
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Sacco C, Galdi A, Orgiani P, Coppola N, Wei HI, Arpaia R, Charpentier S, Lombardi F, Goodge B, Kourkoutis LF, Shen K, Schlom DG, Maritato L. Low temperature hidden Fermi-liquid charge transport in under doped La x Sr 1-x CuO 2 infinite layer electron-doped thin films. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:445601. [PMID: 31295728 DOI: 10.1088/1361-648x/ab3132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We have studied the low temperature electrical transport properties of La x Sr1-x CuO2 thin films grown by oxide molecular beam epitaxy on (1 1 0) GdScO3 and TbScO3 substrates. The transmission electron microscopy measurements and the x-ray diffraction analysis confirmed the epitaxy of the obtained films and the study of their normal state transport properties, removing the ambiguity regarding the truly conducting layer, allowed to highlight the presence of a robust hidden Fermi liquid charge transport in the low temperature properties of infinite layer electron doped cuprate superconductors. These results are in agreement with recent observations performed in other p and n doped cuprate materials and point toward a general description of the superconducting and normal state properties in these compounds.
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Affiliation(s)
- C Sacco
- Department of Industrial Engineering, University of Salerno, Fisciano (SA), Italy. CNR-SPIN, UOS Salerno, Fisciano (SA), Italy
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14
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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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15
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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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16
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Modic KA, Bachmann MD, Ramshaw BJ, Arnold F, Shirer KR, Estry A, Betts JB, Ghimire NJ, Bauer ED, Schmidt M, Baenitz M, Svanidze E, McDonald RD, Shekhter A, Moll PJW. Resonant torsion magnetometry in anisotropic quantum materials. Nat Commun 2018; 9:3975. [PMID: 30266902 PMCID: PMC6162279 DOI: 10.1038/s41467-018-06412-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 08/29/2018] [Indexed: 11/09/2022] Open
Abstract
Unusual behavior in quantum materials commonly arises from their effective low-dimensional physics, reflecting the underlying anisotropy in the spin and charge degrees of freedom. Here we introduce the magnetotropic coefficient k = ∂2F/∂θ2, the second derivative of the free energy F with respect to the magnetic field orientation θ in the crystal. We show that the magnetotropic coefficient can be quantitatively determined from a shift in the resonant frequency of a commercially available atomic force microscopy cantilever under magnetic field. This detection method enables part per 100 million sensitivity and the ability to measure magnetic anisotropy in nanogram-scale samples, as demonstrated on the Weyl semimetal NbP. Measurement of the magnetotropic coefficient in the spin-liquid candidate RuCl3 highlights its sensitivity to anisotropic phase transitions and allows a quantitative comparison to other thermodynamic coefficients via the Ehrenfest relations.
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Affiliation(s)
- K A Modic
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany.
| | - Maja D Bachmann
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | - B J Ramshaw
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA
| | - F Arnold
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | - K R Shirer
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | - Amelia Estry
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | - J B Betts
- Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Nirmal J Ghimire
- Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.,Argonne National Laboratory, Lemont, IL, 60439, USA
| | - E D Bauer
- Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Marcus Schmidt
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | - Michael Baenitz
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | - E Svanidze
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany
| | | | - Arkady Shekhter
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310, USA
| | - Philip J W Moll
- Max-Planck-Institute for Chemical Physics of Solids, Noethnitzer Strasse 40, D-01187, Dresden, Germany. .,EPFL STI IMX-GE MXC 240, CH-1015, Lausanne, Switzerland.
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17
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Giraldo-Gallo P, Galvis JA, Stegen Z, Modic KA, Balakirev FF, Betts JB, Lian X, Moir C, Riggs SC, Wu J, Bollinger AT, He X, Božović I, Ramshaw BJ, McDonald RD, Boebinger GS, Shekhter A. Scale-invariant magnetoresistance in a cuprate superconductor. Science 2018; 361:479-481. [PMID: 30072535 DOI: 10.1126/science.aan3178] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/31/2018] [Indexed: 11/02/2022]
Abstract
The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La2-x Sr x CuO4 cuprate in the vicinity of the critical doping, 0.161 ≤ p ≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.
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Affiliation(s)
- P Giraldo-Gallo
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.,Department of Physics, Universidad de Los Andes, Bogotá 111711, Colombia
| | - J A Galvis
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.,Departamento de Ciencias Naturales, Facultad de Ingeniería y Ciencias Básicas, Universidad Central, Bogotá 110311, Colombia
| | - Z Stegen
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.,Department of Physics, Florida State University, Tallahassee, FL 32310, USA
| | - K A Modic
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - F F Balakirev
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - J B Betts
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - X Lian
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.,Department of Physics, Florida State University, Tallahassee, FL 32310, USA
| | - C Moir
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.,Department of Physics, Florida State University, Tallahassee, FL 32310, USA
| | - S C Riggs
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA
| | - J Wu
- Brookhaven National Laboratory (BNL), Upton, NY 11973, USA
| | - A T Bollinger
- Brookhaven National Laboratory (BNL), Upton, NY 11973, USA
| | - X He
- Brookhaven National Laboratory (BNL), Upton, NY 11973, USA.,Applied Physics Department, Yale University, New Haven, CT 06520, USA
| | - I Božović
- Brookhaven National Laboratory (BNL), Upton, NY 11973, USA.,Applied Physics Department, Yale University, New Haven, CT 06520, USA
| | - B J Ramshaw
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA.,Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA
| | - R D McDonald
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - G S Boebinger
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.,Department of Physics, Florida State University, Tallahassee, FL 32310, USA
| | - A Shekhter
- National High Magnetic Field Laboratory (NHMFL), Florida State University, Tallahassee, FL 32310, USA.
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18
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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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19
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Quantum limit transport and destruction of the Weyl nodes in TaAs. Nat Commun 2018; 9:2217. [PMID: 29880848 PMCID: PMC5992152 DOI: 10.1038/s41467-018-04542-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 05/03/2018] [Indexed: 11/09/2022] Open
Abstract
Weyl fermions are a recently discovered ingredient for correlated states of electronic matter. A key difficulty has been that real materials also contain non-Weyl quasiparticles, and disentangling the experimental signatures has proven challenging. Here we use magnetic fields up to 95 T to drive the Weyl semimetal TaAs far into its quantum limit, where only the purely chiral 0th Landau levels of the Weyl fermions are occupied. We find the electrical resistivity to be nearly independent of magnetic field up to 50 T: unusual for conventional metals but consistent with the chiral anomaly for Weyl fermions. Above 50 T we observe a two-order-of-magnitude increase in resistivity, indicating that a gap opens in the chiral Landau levels. Above 80 T we observe strong ultrasonic attenuation below 2 K, suggesting a mesoscopically textured state of matter. These results point the way to inducing new correlated states of matter in the quantum limit of Weyl semimetals.
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20
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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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21
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Hussey NE, Buhot J, Licciardello S. A tale of two metals: contrasting criticalities in the pnictides and hole-doped cuprates. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:052501. [PMID: 29353812 DOI: 10.1088/1361-6633/aaa97c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The iron-based high temperature superconductors share a number of similarities with their copper-based counterparts, such as reduced dimensionality, proximity to states of competing order, and a critical role for 3d electron orbitals. Their respective temperature-doping phase diagrams also contain certain commonalities that have led to claims that the metallic and superconducting (SC) properties of both families are governed by their proximity to a quantum critical point (QCP) located inside the SC dome. In this review, we critically examine these claims and highlight significant differences in the bulk physical properties of both systems. While there is now a large body of evidence supporting the presence of a (magnetic) QCP in the iron pnictides, the situation in the cuprates is much less apparent, at least for the end point of the pseudogap phase. We argue that the opening of the normal state pseudogap in cuprates, so often tied to a putative QCP, arises from a momentum-dependent breakdown of quasiparticle coherence that sets in at much higher doping levels but which is driven by the proximity to the Mott insulating state at half filling. Finally, we present a new scenario for the cuprates in which this loss of quasiparticle integrity and its evolution with momentum, temperature and doping plays a key role in shaping the resultant phase diagram.
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Affiliation(s)
- N E Hussey
- High Field Magnet Laboratory (HFML-EMFL), Institute for Molecules and Materials, Radboud University, Toernooiveld 7, 6525 ED, Nijmegen, Netherlands
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22
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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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23
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Cai RG, Li L, Wang YQ, Zaanen J. Intertwined Order and Holography: The Case of Parity Breaking Pair Density Waves. PHYSICAL REVIEW LETTERS 2017; 119:181601. [PMID: 29219557 DOI: 10.1103/physrevlett.119.181601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Indexed: 06/07/2023]
Abstract
We present a minimal bottom-up extension of the Chern-Simons bulk action for holographic translational symmetry breaking that naturally gives rise to pair density waves. We construct stationary inhomogeneous black hole solutions in which both the U(1) symmetry and spatially translational symmetry are spontaneously broken at a finite temperature and charge density. This novel solution provides a dual description of a superconducting phase intertwined with charge, current, and parity orders.
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Affiliation(s)
- Rong-Gen Cai
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Li Li
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China
- Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18018, USA
| | - Yong-Qiang Wang
- Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000, China
| | - Jan Zaanen
- Institute Lorentz for Theoretical Physics, Leiden University, P.O. Box 9506, 2300 RA Leiden, The Netherlands
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24
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Elastic evolution of a self-healing ionomer observed via acoustic and ultrasonic resonant spectroscopy. Sci Rep 2017; 7:14417. [PMID: 29089505 PMCID: PMC5663924 DOI: 10.1038/s41598-017-14321-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/09/2017] [Indexed: 11/08/2022] Open
Abstract
Self-healing poly (ethylene co-methacrylic acid) ionomers (EMAA) are thermoplastic materials that when punctured, cut, shot or damaged in a variety of ways, are capable of autonomously reorganizing their physical structure to heal and, in many instances, permanently seal the damaged location. However, a complete picture of the mechanisms responsible for their unusual behavior is not well understood. In this article we report the observation of time dependent acoustic and ultrasonic spectral evolution, measured using resonant acoustic and ultrasonic spectroscopy, for both pre and post-damage EMAA samples. The results provide a means to differentiate healing phases, quantify healing timescales, and potentially elucidate the composition parameters that most significantly impact healing behavior.
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25
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Abstract
The thermal diffusivity in the [Formula: see text] plane of underdoped YBCO crystals is measured by means of a local optical technique in the temperature range of 25-300 K. The phase delay between a point heat source and a set of detection points around it allows for high-resolution measurement of the thermal diffusivity and its in-plane anisotropy. Although the magnitude of the diffusivity may suggest that it originates from phonons, its anisotropy is comparable with reported values of the electrical resistivity anisotropy. Furthermore, the anisotropy drops sharply below the charge order transition, again similar to the electrical resistivity anisotropy. Both of these observations suggest that the thermal diffusivity has pronounced electronic as well as phononic character. At the same time, the small electrical and thermal conductivities at high temperatures imply that neither well-defined electron nor phonon quasiparticles are present in this material. We interpret our results through a strongly interacting incoherent electron-phonon "soup" picture characterized by a diffusion constant [Formula: see text], where [Formula: see text] is the soup velocity, and scattering of both electrons and phonons saturates a quantum thermal relaxation time [Formula: see text].
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26
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Mangin-Thro L, Li Y, Sidis Y, Bourges P. a-b Anisotropy of the Intra-Unit-Cell Magnetic Order in YBa_{2}Cu_{3}O_{6.6}. PHYSICAL REVIEW LETTERS 2017; 118:097003. [PMID: 28306306 DOI: 10.1103/physrevlett.118.097003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Indexed: 06/06/2023]
Abstract
Within the complex phase diagram of the hole-doped cuprates, seizing the nature of the mysterious pseudogap phase is essential for unraveling the microscopic origin of high-temperature superconductivity. Below the pseudogap temperature T^{⋆}, evidence for intra-unit-cell orders breaking the fourfold rotation symmetry have been provided by neutron diffraction and scanning tunneling spectroscopy. Using polarized neutron diffraction on a detwinned YBa_{2}Cu_{3}O_{6.6} sample, we here report a distinct a-b anisotropy of the intra-unit-cell magnetic structure factor below T^{⋆}, highlighting that intra-unit-cell order in this material breaks the mirror symmetry of the CuO_{2} bilayers. This is likely to originate from a crisscrossed arrangement of loop currents within the CuO_{2} bilayer, resulting in a bilayer mean toroidal axis along the b direction.
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Affiliation(s)
- Lucile Mangin-Thro
- Laboratoire Léon Brillouin, CEA-CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Yuan Li
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
| | - Yvan Sidis
- Laboratoire Léon Brillouin, CEA-CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Philippe Bourges
- Laboratoire Léon Brillouin, CEA-CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France
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27
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Varma CM. Quantum-critical fluctuations in 2D metals: strange metals and superconductivity in antiferromagnets and in cuprates. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:082501. [PMID: 27411298 DOI: 10.1088/0034-4885/79/8/082501] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The anomalous transport and thermodynamic properties in the quantum-critical region, in the cuprates, and in the quasi-two dimensional Fe-based superconductors and heavy-fermion compounds, have the same temperature dependences. This can occur only if, despite their vast microscopic differences, a common statistical mechanical model describes their phase transitions. The antiferromagnetic (AFM)-ic models for the latter two, just as the loop-current model for the cuprates, map to the dissipative XY model. The solution of this model in (2+1)D reveals that the critical fluctuations are determined by topological excitations, vortices and a variety of instantons, and not by renormalized spin-wave theories of the Landau-Ginzburg-Wilson type, adapted by Moriya, Hertz and others for quantum-criticality. The absorptive part of the fluctuations is a separable function of momentum [Formula: see text], measured from the ordering vector, and of the frequency ω and the temperature T which scale as [Formula: see text] at criticality. Direct measurements of the fluctuations by neutron scattering in the quasi-two-dimensional heavy fermion and Fe-based compounds, near their antiferromagnetic quantum critical point, are consistent with this form. Such fluctuations, together with the vertex coupling them to fermions, lead to a marginal fermi-liquid, with the imaginary part of the self-energy [Formula: see text] for all momenta, a resistivity [Formula: see text], a [Formula: see text] contribution to the specific heat, and other singular fermi-liquid properties common to these diverse compounds, as well as to d-wave superconductivity. This is explicitly verified, in the cuprates, by analysis of the pairing and the normal self-energy directly extracted from the recent high resolution angle resolved photoemission measurements. This reveals, in agreement with the theory, that the frequency dependence of the attractive irreducible particle-particle vertex in the d-wave channel is the same as the irreducible particle-hole vertex in the full symmetry of the lattice.
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Affiliation(s)
- Chandra M Varma
- Department of Physics and Astronomy, University of California, Riverside, CA 92521, USA
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28
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Pascarelli S, Mathon O, Mairs T, Kantor I, Agostini G, Strohm C, Pasternak S, Perrin F, Berruyer G, Chappelet P, Clavel C, Dominguez MC. The Time-resolved and Extreme-conditions XAS (TEXAS) facility at the European Synchrotron Radiation Facility: the energy-dispersive X-ray absorption spectroscopy beamline ID24. JOURNAL OF SYNCHROTRON RADIATION 2016; 23:353-68. [PMID: 26698085 PMCID: PMC5297599 DOI: 10.1107/s160057751501783x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/23/2015] [Indexed: 05/27/2023]
Abstract
The European Synchrotron Radiation Facility has recently made available to the user community a facility totally dedicated to Time-resolved and Extreme-conditions X-ray Absorption Spectroscopy--TEXAS. Based on an upgrade of the former energy-dispersive XAS beamline ID24, it provides a unique experimental tool combining unprecedented brilliance (up to 10(14) photons s(-1) on a 4 µm × 4 µm FWHM spot) and detection speed for a full EXAFS spectrum (100 ps per spectrum). The science mission includes studies of processes down to the nanosecond timescale, and investigations of matter at extreme pressure (500 GPa), temperature (10000 K) and magnetic field (30 T). The core activities of the beamline are centered on new experiments dedicated to the investigation of extreme states of matter that can be maintained only for very short periods of time. Here the infrastructure, optical scheme, detection systems and sample environments used to enable the mission-critical performance are described, and examples of first results on the investigation of the electronic and local structure in melts at pressure and temperature conditions relevant to the Earth's interior and in laser-shocked matter are given.
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Affiliation(s)
- S. Pascarelli
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - O. Mathon
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - T. Mairs
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - I. Kantor
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - G. Agostini
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - C. Strohm
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
- Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - S. Pasternak
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - F. Perrin
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - G. Berruyer
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - P. Chappelet
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - C. Clavel
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - M. C. Dominguez
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
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Varma CM. Quantum Criticality in Quasi-Two-Dimensional Itinerant Antiferromagnets. PHYSICAL REVIEW LETTERS 2015; 115:186405. [PMID: 26565482 DOI: 10.1103/physrevlett.115.186405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Indexed: 06/05/2023]
Abstract
Quasi-two-dimensional itinerant fermions in the antiferromagnetic (AFM) quantum-critical region of their phase diagram, such as in the Fe-based superconductors or in some of the heavy-fermion compounds, exhibit a resistivity varying linearly with temperature and a contribution to specific heat or thermopower proportional to TlnT. It is shown, here, that a generic model of itinerant anti-ferromagnet can be canonically transformed so that its critical fluctuations around the AFM-vector Q can be obtained from the fluctuations in the long wavelength limit of a dissipative quantum XY model. The fluctuations of the dissipative quantum XY model in 2D have been evaluated recently, and in a large regime of parameters, they are determined, not by renormalized spin fluctuations, but by topological excitations. In this regime, the fluctuations are separable in their spatial and temporal dependence and have a spatial correlation length which is proportional to the logarithm of the temporal correlation length, i.e., for some purposes, the effective dynamic exponent z=∞. The time dependence gives ω/T scaling at criticality. The observed resistivity and entropy then follow. Several predictions to test the theory are also given.
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Affiliation(s)
- C M Varma
- Department of Physics and Astronomy, University of California, Riverside, California 92521, USA
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30
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Kondo T, Malaeb W, Ishida Y, Sasagawa T, Sakamoto H, Takeuchi T, Tohyama T, Shin S. Point nodes persisting far beyond Tc in Bi2212. Nat Commun 2015; 6:7699. [PMID: 26158431 PMCID: PMC4510699 DOI: 10.1038/ncomms8699] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 06/01/2015] [Indexed: 11/26/2022] Open
Abstract
In contrast to a complex feature of antinodal state, suffering from competing orders, the pairing gap of cuprates is obtained in the nodal region, which therefore holds the key to the superconducting mechanism. One of the biggest question is whether the point nodal state as a hallmark of d-wave pairing collapses at Tc like the BCS-type superconductors, or it instead survives above Tc turning into the preformed pair state. A difficulty in this issue comes from the small magnitude of the nodal gap, which has been preventing experimentalists from solving it. Here we use a laser ARPES capable of ultrahigh-energy resolution, and detect the point nodes surviving far beyond Tc in Bi2212. By tracking the temperature evolution of spectra, we reveal that the superconductivity occurs when the pair-breaking rate is suppressed smaller than the single-particle scattering rate on cooling, which governs the value of Tc in cuprates. The pairing gap of the high-Tc cuprates has been expected to close at the transition temperature, similarly to the case of conventional superconductors. Here the authors perform ARPES measurements on Bi2212, and reveal a point nodal gap formation beyond Tc, characterized in terms of three parameters.
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Affiliation(s)
- Takeshi Kondo
- ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - W Malaeb
- ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Y Ishida
- ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - T Sasagawa
- Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan
| | - H Sakamoto
- Department of Crystalline Materials Science, Nagoya University, Nagoya 464-8603, Japan
| | - Tsunehiro Takeuchi
- Energy Materials Laboratory, Toyota Technological Institute, Nagoya 468-8511, Japan
| | - T Tohyama
- Department of Applied Physics, Tokyo University of Science, Tokyo 125-8585, Japan
| | - S Shin
- ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
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31
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Mangin-Thro L, Sidis Y, Wildes A, Bourges P. Intra-unit-cell magnetic correlations near optimal doping in YBa2Cu3O6.85. Nat Commun 2015; 6:7705. [PMID: 26138869 PMCID: PMC4506545 DOI: 10.1038/ncomms8705] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 06/01/2015] [Indexed: 11/09/2022] Open
Abstract
The pseudo-gap phenomenon in copper oxide superconductors is central to any description of these materials as it prefigures the superconducting state itself. A magnetic intra-unit-cell order was found to occur just at the pseudo-gap temperature in four cuprate high-Tc superconducting families. Here we present polarized neutron-scattering measurements of nearly optimally doped YBa2Cu3O6.85, carried out on two different spectrometers, that reveal several features. The intra-unit-cell order consists of finite-sized planar domains that are very weakly correlated along the c axis. At high temperature, only the out-of-plane magnetic components correlate, indicating a strong Ising anisotropy. An aditional in-plane response develops at low temperature, giving rise to an apparent tilt of the magnetic moment. The discovery of these two regimes puts stringent constraints, which are tightly bound to the pseudo-gap physics, on the intrinsic nature of intra-unit-cell order. The pseudo-gap phenomenon is central to the description of high-Tc superconductivity in copper oxides. Here, the authors investigate nearly optimally doped YBCO using polarized neutron scattering to characterize intra-unit-cell magnetic correlations in relation with the pseudo-gap temperature.
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Affiliation(s)
- L Mangin-Thro
- Laboratoire Léon Brillouin, IRAMIS/LLB, UMR12, CEA-CNRS, CEA-Saclay, Gif sur Yvette 91191, France
| | - Y Sidis
- Laboratoire Léon Brillouin, IRAMIS/LLB, UMR12, CEA-CNRS, CEA-Saclay, Gif sur Yvette 91191, France
| | - A Wildes
- Institut Laue-Langevin, 71 avenue des martyrs, Grenoble 38000, France
| | - P Bourges
- Laboratoire Léon Brillouin, IRAMIS/LLB, UMR12, CEA-CNRS, CEA-Saclay, Gif sur Yvette 91191, France
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32
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Specific heat and sound velocity at the relevant competing phase of high-temperature superconductors. Proc Natl Acad Sci U S A 2015; 112:6331-5. [PMID: 25941376 DOI: 10.1073/pnas.1417150112] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent highly accurate sound velocity measurements reveal a phase transition to a competing phase in YBa2Cu3O6+δ that is not identified in available specific heat measurements. We show that this signature is consistent with the universality class of the loop current-ordered state when the free-energy reduction is similar to the superconducting condensation energy, due to the anomalous fluctuation region of such a transition. We also compare the measured specific heat with some usual types of transitions, which are observed at lower temperatures in some cuprates, and find that the upper limit of the energy reduction due to them is about 1/40th the superconducting condensation energy.
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33
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Benhabib S, Sacuto A, Civelli M, Paul I, Cazayous M, Gallais Y, Méasson MA, Zhong RD, Schneeloch J, Gu GD, Colson D, Forget A. Collapse of the normal-state pseudogap at a Lifshitz transition in the Bi(2)Sr(2)CaCu(2)O(8+δ) cuprate superconductor. PHYSICAL REVIEW LETTERS 2015; 114:147001. [PMID: 25910152 DOI: 10.1103/physrevlett.114.147001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Indexed: 06/04/2023]
Abstract
We report a fine tuned doping study of strongly overdoped Bi_{2}Sr_{2}CaCu_{2}O_{8+δ} single crystals using electronic Raman scattering. Combined with theoretical calculations, we show that the doping, at which the normal-state pseudogap closes, coincides with a Lifshitz quantum phase transition where the active holelike Fermi surface becomes electronlike. This conclusion suggests that the microscopic cause of the pseudogap is sensitive to the Fermi surface topology. Furthermore, we find that the superconducting transition temperature is unaffected by this transition, demonstrating that their origins are different on the overdoped side.
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Affiliation(s)
- S Benhabib
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - A Sacuto
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M Civelli
- Laboratoire de Physique des Solides, UMR 8502 CNRS, Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - I Paul
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M Cazayous
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - Y Gallais
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M-A Méasson
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - R D Zhong
- Matter Physics and Materials Science, Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
| | - J Schneeloch
- Matter Physics and Materials Science, Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
| | - G D Gu
- Matter Physics and Materials Science, Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
| | - D Colson
- Service de Physique de l'Etat Condensé, CEA-Saclay, 91191 Gif-sur-Yvette, France
| | - A Forget
- Service de Physique de l'Etat Condensé, CEA-Saclay, 91191 Gif-sur-Yvette, France
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34
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Ramshaw BJ, Sebastian SE, McDonald RD, Day J, Tan BS, Zhu Z, Betts JB, Liang R, Bonn DA, Hardy WN, Harrison N. Quasiparticle mass enhancement approaching optimal doping in a high-Tc superconductor. Science 2015; 348:317-20. [DOI: 10.1126/science.aaa4990] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/16/2015] [Indexed: 11/02/2022]
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35
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Abstract
The d and f electrons in correlated metals are often neither fully localized around their host nuclei nor fully itinerant. This localized/itinerant duality underlies the correlated electronic states of the high-Tc cuprate superconductors and the heavy-fermion intermetallics and is nowhere more apparent than in the 5f valence electrons of plutonium. Here, we report the full set of symmetry-resolved elastic moduli of PuCoGa5--the highest Tc superconductor of the heavy fermions (Tc = 18.5 K)--and find that the bulk modulus softens anomalously over a wide range in temperature above Tc. The elastic symmetry channel in which this softening occurs is characteristic of a valence instability--therefore, we identify the elastic softening with fluctuations of the plutonium 5f mixed-valence state. These valence fluctuations disappear when the superconducting gap opens at Tc, suggesting that electrons near the Fermi surface play an essential role in the mixed-valence physics of this system and that PuCoGa5 avoids a valence transition by entering the superconducting state. The lack of magnetism in PuCoGa5 has made it difficult to reconcile with most other heavy-fermion superconductors, where superconductivity is generally believed to be mediated by magnetic fluctuations. Our observations suggest that valence fluctuations play a critical role in the unusually high Tc of PuCoGa5.
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36
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Incipient charge order observed by NMR in the normal state of YBa2Cu3Oy. Nat Commun 2015; 6:6438. [PMID: 25751448 PMCID: PMC4366503 DOI: 10.1038/ncomms7438] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 01/28/2015] [Indexed: 11/08/2022] Open
Abstract
The pseudogap regime of high-temperature cuprates harbours diverse manifestations of electronic ordering whose exact nature and universality remain debated. Here, we show that the short-ranged charge order recently reported in the normal state of YBa2Cu3Oy corresponds to a truly static modulation of the charge density. We also show that this modulation impacts on most electronic properties, that it appears jointly with intra-unit-cell nematic, but not magnetic, order, and that it exhibits differences with the charge density wave observed at lower temperatures in high magnetic fields. These observations prove mostly universal, they place new constraints on the origin of the charge density wave and they reveal that the charge modulation is pinned by native defects. Similarities with results in layered metals such as NbSe2, in which defects nucleate halos of incipient charge density wave at temperatures above the ordering transition, raise the possibility that order-parameter fluctuations, but no static order, would be observed in the normal state of most cuprates if disorder were absent.
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37
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Hashimoto M, Nowadnick EA, He RH, Vishik IM, Moritz B, He Y, Tanaka K, Moore RG, Lu D, Yoshida Y, Ishikado M, Sasagawa T, Fujita K, Ishida S, Uchida S, Eisaki H, Hussain Z, Devereaux TP, Shen ZX. Direct spectroscopic evidence for phase competition between the pseudogap and superconductivity in Bi2Sr2CaCu2O(8+δ). NATURE MATERIALS 2015; 14:37-42. [PMID: 25362356 DOI: 10.1038/nmat4116] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 09/19/2014] [Indexed: 06/04/2023]
Abstract
In the high-temperature (T(c)) cuprate superconductors, a growing body of evidence suggests that the pseudogap phase, existing below the pseudogap temperature T*, is characterized by some broken electronic symmetries distinct from those associated with superconductivity. In particular, recent scattering experiments have suggested that charge ordering competes with superconductivity. However, no direct link of an interplay between the two phases has been identified from the important low-energy excitations. Here, we report an antagonistic singularity at T(c) in the spectral weight of Bi2Sr2CaCu2O(8+δ) as compelling evidence for phase competition, which persists up to a high hole concentration p ~ 0.22. Comparison with theoretical calculations confirms that the singularity is a signature of competition between the order parameters for the pseudogap and superconductivity. The observation of the spectroscopic singularity at finite temperatures over a wide doping range provides new insights into the nature of the competitive interplay between the two orders and the complex phase diagram near the pseudogap critical point.
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Affiliation(s)
- Makoto Hashimoto
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Elizabeth A Nowadnick
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA [3] Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA
| | - Rui-Hua He
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA [3] Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA [4] Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Inna M Vishik
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA [3] Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA
| | - Brian Moritz
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Department of Physics and Astrophysics, University of North Dakota, Grand Forks, North Dakota 58202, USA
| | - Yu He
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA [3] Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA
| | - Kiyohisa Tanaka
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA [3] Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA [4] Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Robert G Moore
- 1] Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Donghui Lu
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Yoshiyuki Yoshida
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568, Japan
| | - Motoyuki Ishikado
- 1] National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568, Japan [2] Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Takao Sasagawa
- Materials and Structures Laboratory, Tokyo institute of Technology, Yokohama, Kanagawa 226-8503, Japan
| | - Kazuhiro Fujita
- 1] Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan [2] Laboratory for Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Shigeyuki Ishida
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shinichi Uchida
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroshi Eisaki
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568, Japan
| | - Zahid Hussain
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Thomas P Devereaux
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
| | - Zhi-Xun Shen
- 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA [3] Departments of Physics and Applied Physics, Stanford University, Stanford, California 94305, USA
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38
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Chan MK, Veit MJ, Dorow CJ, Ge Y, Li Y, Tabis W, Tang Y, Zhao X, Barišić N, Greven M. In-plane magnetoresistance obeys Kohler's rule in the pseudogap phase of cuprate superconductors. PHYSICAL REVIEW LETTERS 2014; 113:177005. [PMID: 25379934 DOI: 10.1103/physrevlett.113.177005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Indexed: 06/04/2023]
Abstract
We report in-plane resistivity (ρ) and transverse magnetoresistance (MR) measurements for underdoped HgBa(2)CuO(4+δ) (Hg1201). Contrary to the long-standing view that Kohler's rule is strongly violated in underdoped cuprates, we find that it is in fact satisfied in the pseudogap phase of Hg1201. The transverse MR shows a quadratic field dependence, δρ/ρ(0)=aH(2), with a(T)∝T(-4). In combination with the observed ρ∝T(2) dependence, this is consistent with a single Fermi-liquid quasiparticle scattering rate. We show that this behavior is typically masked in cuprates with lower structural symmetry or strong disorder effects.
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Affiliation(s)
- M K Chan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M J Veit
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - C J Dorow
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Y Ge
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Y Li
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - W Tabis
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA and AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. A. Mickiewicza 30, 30-059 Krakow, Poland
| | - Y Tang
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - X Zhao
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA and State Key Lab of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, China
| | - N Barišić
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA and Service de Physique de l'Etat Condensé, CEA-DSM-IRAMIS, F 91198 Gif-sur-Yvette, France and Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
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39
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Kirzhner T, Koren G. Pairing and the phase diagram of the normal coherence length ξN(T, x) above Tc of La(2-x)Sr(x)CuO4 thin films probed by the Josephson effect. Sci Rep 2014; 4:6244. [PMID: 25175417 PMCID: PMC4150101 DOI: 10.1038/srep06244] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 08/08/2014] [Indexed: 11/09/2022] Open
Abstract
The long range proximity effect in high-Tc c-axis Josephson junctions with a high-Tc barrier of lower Tc is still a puzzling phenomenon. It leads to supercurrents in junctions with much thicker barriers than would be allowed by the conventional proximity effect. Here we measured the T − x (Temperature-doping level) phase diagram of the barrier coherence length ξN(T, x), and found an enhancement of ξN at moderate under-doping and high temperatures. This indicates that a possible origin of the long range proximity effect in the cuprate barrier is the conjectured pre-formed pairs in the pseudogap regime, which increase the length scale over which superconducting correlations survive in the seemingly normal barrier. In more details, we measured the supercurrents Ic of Superconducting - Normal - Superconducting SNS c-axis junctions, where S was optimally doped Y Ba2Cu3O7−δ below Tc (90 K) and N was La2−xSrxCuO4 above its Tc (<25 K) but in the pseudogap regime. From the exponential decay of Ic(T) ∝ exp[−d/ξN(T)], where d is the barrier thickness, the ξN(T) values were extracted. By repeating these measurements for different barrier doping levels x, the whole phase diagram of ξN(T, x) was obtained.
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Affiliation(s)
- Tal Kirzhner
- Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Gad Koren
- Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel
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40
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Cilento F, Dal Conte S, Coslovich G, Peli S, Nembrini N, Mor S, Banfi F, Ferrini G, Eisaki H, Chan MK, Dorow CJ, Veit MJ, Greven M, van der Marel D, Comin R, Damascelli A, Rettig L, Bovensiepen U, Capone M, Giannetti C, Parmigiani F. Photo-enhanced antinodal conductivity in the pseudogap state of high-Tc cuprates. Nat Commun 2014; 5:4353. [PMID: 25014895 PMCID: PMC4104437 DOI: 10.1038/ncomms5353] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 06/07/2014] [Indexed: 11/24/2022] Open
Abstract
A major challenge in understanding the cuprate superconductors is to clarify the nature of the fundamental electronic correlations that lead to the pseudogap phenomenon. Here we use ultrashort light pulses to prepare a non-thermal distribution of excitations and capture novel properties that are hidden at equilibrium. Using a broadband (0.5–2 eV) probe, we are able to track the dynamics of the dielectric function and unveil an anomalous decrease in the scattering rate of the charge carriers in a pseudogap-like region of the temperature (T) and hole-doping (p) phase diagram. In this region, delimited by a well-defined T*neq(p) line, the photoexcitation process triggers the evolution of antinodal excitations from gapped (localized) to delocalized quasiparticles characterized by a longer lifetime. The novel concept of photo-enhanced antinodal conductivity is naturally explained within the single-band Hubbard model, in which the short-range Coulomb repulsion leads to a k-space differentiation between nodal quasiparticles and antinodal excitations. The pseudogap phase exhibited by the cuprates is almost as enigmatic as superconductivity in these materials itself. A time-resolved study performed by Cilento et al. suggests that this state can be photoexcited into a transient non-equilibrium state that is more conductive than the equilibrium state.
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Affiliation(s)
- F Cilento
- Elettra-Sincrotrone Trieste S.C.p.A., I-34149 Basovizza, Italy
| | - S Dal Conte
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [3]
| | - G Coslovich
- 1] Department of Physics, Università degli Studi di Trieste, I-34127 Trieste, Italy [2]
| | - S Peli
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] Department of Physics, Università degli Studi di Milano, I-20133 Milano, Italy
| | - N Nembrini
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] Department of Physics, Università degli Studi di Milano, I-20133 Milano, Italy
| | - S Mor
- Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - F Banfi
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - G Ferrini
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - H Eisaki
- Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan
| | - M K Chan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - C J Dorow
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M J Veit
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - D van der Marel
- Département de Physique de la Matière Condensée, Université de Genève, CH1211 Genève, Switzerland
| | - R Comin
- 1] Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 [2] Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - A Damascelli
- 1] Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 [2] Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - L Rettig
- 1] Fakultaet fuer Physik and Zentrum für Nanointegration (CENIDE), Universitaet Duisburg-Essen, 47048 Duisburg, Germany [2]
| | - U Bovensiepen
- Fakultaet fuer Physik and Zentrum für Nanointegration (CENIDE), Universitaet Duisburg-Essen, 47048 Duisburg, Germany
| | - M Capone
- CNR-IOM Democritos National Simulation Center and Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea 265, 34136 Trieste, Italy
| | - C Giannetti
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - F Parmigiani
- 1] Elettra-Sincrotrone Trieste S.C.p.A., I-34149 Basovizza, Italy [2] Department of Physics, Università degli Studi di Trieste, I-34127 Trieste, Italy
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Fujita K, Kim CK, Lee I, Lee J, Hamidian MH, Firmo IA, Mukhopadhyay S, Eisaki H, Uchida S, Lawler MJ, Kim EA, Davis JC. Simultaneous transitions in cuprate momentum-space topology and electronic symmetry breaking. Science 2014; 344:612-6. [PMID: 24812397 DOI: 10.1126/science.1248783] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The existence of electronic symmetry breaking in the underdoped cuprates and its disappearance with increased hole density p are now widely reported. However, the relation between this transition and the momentum-space (k-space) electronic structure underpinning the superconductivity has not yet been established. Here, we visualize the Q = 0 (intra-unit-cell) and Q ≠ 0 (density-wave) broken-symmetry states, simultaneously with the coherent k-space topology, for Bi₂Sr₂CaCu₂O(8+δ) samples spanning the phase diagram 0.06 ≤ p ≤ 0.23. We show that the electronic symmetry-breaking tendencies weaken with increasing p and disappear close to a critical doping p(c) = 0.19. Concomitantly, the coherent k-space topology undergoes an abrupt transition, from arcs to closed contours, at the same p(c). These data reveal that the k-space topology transformation in cuprates is linked intimately with the disappearance of the electronic symmetry breaking at a concealed critical point.
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Affiliation(s)
- K Fujita
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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Karapetyan H, Xia J, Hücker M, Gu GD, Tranquada JM, Fejer MM, Kapitulnik A. Evidence of chiral order in the charge-ordered phase of superconducting La1.875Ba0.125Cuo4 single crystals using polar Kerr-effect measurements. PHYSICAL REVIEW LETTERS 2014; 112:047003. [PMID: 24580482 DOI: 10.1103/physrevlett.112.047003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Indexed: 06/03/2023]
Abstract
High resolution polar Kerr effect measurements were performed on La1.875Ba0.125CuO4 single crystals revealing that a finite Kerr signal is measured below an onset temperature TK that coincides with the charge ordering transition temperature TCO. We further show that the sign of the Kerr signal cannot be trained with the magnetic field, is found to be the same on opposite sides of the same crystal, and is odd with respect to strain in the diagonal direction of the unit cell. These observations are consistent with a chiral "gyrotropic" order above Tc for La1.875Ba0.125CuO4; similarities to other cuprates suggest that it is a universal property in the pseudogap regime.
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Affiliation(s)
- Hovnatan Karapetyan
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA and Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Jing Xia
- Department of Physics and Astronomy, University of California, Irvine, California 92697-4575, USA
| | - M Hücker
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - G D Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - J M Tranquada
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - M M Fejer
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
| | - A Kapitulnik
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA and Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA and Department of Physics, Stanford University, Stanford, California 94305, USA
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