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Tseng Y, Paris E, Schmidt KP, Zhang W, Asmara TC, Bag R, Strocov VN, Singh S, Schlappa J, Rønnow HM, Schmitt T. Momentum-resolved spin-conserving two-triplon bound state and continuum in a cuprate ladder. COMMUNICATIONS PHYSICS 2023; 6:138. [PMID: 38665396 PMCID: PMC11041747 DOI: 10.1038/s42005-023-01250-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 05/23/2023] [Indexed: 04/28/2024]
Abstract
Studying multi-particle elementary excitations has provided unique access to understand collective many-body phenomena in correlated electronic materials, paving the way towards constructing microscopic models. In this work, we perform O K-edge resonant inelastic X-ray scattering (RIXS) on the quasi-one-dimensional cuprate Sr 14 Cu 24 O 41 with weakly-doped spin ladders. The RIXS signal is dominated by a dispersing sharp mode ~ 270 meV on top of a damped incoherent component ~ 400-500 meV. Comparing with model calculations using the perturbative continuous unitary transformations method, the two components resemble the spin-conserving ΔS = 0 two-triplon bound state and continuum excitations in the spin ladders. Such multi-spin response with long-lived ΔS = 0 excitons is central to several exotic magnetic properties featuring Majorana fermions, yet remains unexplored given the generally weak cross-section with other experimental techniques. By investigating a simple spin-ladder model system, our study provides valuable insight into low-dimensional quantum magnetism.
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Affiliation(s)
- Yi Tseng
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Present Address: Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Eugenio Paris
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
| | - Kai P. Schmidt
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Staudtstraße 7, D-91058 Erlangen, Germany
| | - Wenliang Zhang
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
| | - Teguh Citra Asmara
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
| | - Rabindranath Bag
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, Maharashtra 411008 India
- Present Address: Department of Physics, Duke University, Durham, NC 27708 USA
| | - Vladimir N. Strocov
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
| | - Surjeet Singh
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, Maharashtra 411008 India
| | - Justine Schlappa
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
- European X-Ray Free-Electron Laser Facility GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Henrik M. Rønnow
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Thorsten Schmitt
- Photon Science Division, Paul Scherrer Institut, Forschungstrasse 111, CH-5232 Villigen PSI, Switzerland
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Adamus P, Xu B, Marsik P, Dubroka A, Barabasová P, Růžičková H, Puphal P, Pomjakushina E, Tallon JL, Mathis YL, Munzar D, Bernhard C. Analogies of phonon anomalies and electronic gap features in the infrared response of Sr14-xCa xCu 24O 41and underdoped YBa 2Cu 3O6+x. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 86:044502. [PMID: 36821858 DOI: 10.1088/1361-6633/acbe4f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
We present an experimental and theoretical study which compares the phonon anomalies and the electronic gap features in the infrared response of the weakly coupled two-leg-ladders in Sr14-xCaxCu24O41(SCCO) with those of the underdoped high-Tcsuperconductor YBa2Cu3O6+x(YBCO) and thereby reveals some surprising analogies. Specifically, we present a phenomenological model that describes the anomalous doping- and temperature-dependence of some of the phonon features in thea-axis response (field along the rungs of the ladders) of SCCO. It assumes that the phonons are coupled to charge oscillations within the ladders. Their changes with decreasing temperature reveal the formation of a crystal (density wave) of hole pairs that are oriented along the rungs. We also discuss the analogy to a similar model that was previously used to explain the phonon anomalies and an electronic plasma mode in thec-axis response (field perpendicular to the CuO2planes) of YBCO. We further confirm that an insulator-like pseudogap develops in thea-axis conductivity of SCCO which closely resembles that in thec-axis conductivity of YBCO. Most surprisingly, we find that thec-axis conductivity (field along the legs of the ladders) of SCCO is strikingly similar to the in-plane one (field parallel to the CuO2planes) of YBCO. Notably, in both cases a dip feature develops in the normal state spectra that is connected with a spectral weight shift toward low frequencies and can thus be associated with precursor superconducting pairing correlations that are lacking macroscopic phase coherence. This SCCO-YBCO analogy indicates that collective degrees of freedom contribute to the low-energy response of underdoped highTccuprates and it even suggests that the charges in the CuO2planes tend to segregate forming quasi-one-dimensional structures similar to the two-leg ladders, as predicted for the stripe-scenario or certain intertwinned states.
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Affiliation(s)
- Petr Adamus
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Bing Xu
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Premysl Marsik
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - Adam Dubroka
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Paulína Barabasová
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Hana Růžičková
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Pascal Puphal
- Laboratory for Multiscale Materials Experiments, PSI, 5232 Villigen, Switzerland
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | | | - Jeffery L Tallon
- Victoria University of Wellington, Robinson Research Institute, POB 33436, Lower Hutt 5046, New Zealand
| | - Yves-Laurent Mathis
- Karlsruhe Institute of Technology, Institute for Beam Physics and Technology, Hermann-von-Helmhotz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Dominik Munzar
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Christian Bernhard
- University of Fribourg, Department of Physics, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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3
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Magnetically mediated hole pairing in fermionic ladders of ultracold atoms. Nature 2023; 613:463-467. [PMID: 36653561 PMCID: PMC9849138 DOI: 10.1038/s41586-022-05437-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 10/11/2022] [Indexed: 01/20/2023]
Abstract
Conventional superconductivity emerges from pairing of charge carriers-electrons or holes-mediated by phonons1. In many unconventional superconductors, the pairing mechanism is conjectured to be mediated by magnetic correlations2, as captured by models of mobile charges in doped antiferromagnets3. However, a precise understanding of the underlying mechanism in real materials is still lacking and has been driving experimental and theoretical research for the past 40 years. Early theoretical studies predicted magnetic-mediated pairing of dopants in ladder systems4-8, in which idealized theoretical toy models explained how pairing can emerge despite repulsive interactions9. Here we experimentally observe this long-standing theoretical prediction, reporting hole pairing due to magnetic correlations in a quantum gas of ultracold atoms. By engineering doped antiferromagnetic ladders with mixed-dimensional couplings10, we suppress Pauli blocking of holes at short length scales. This results in a marked increase in binding energy and decrease in pair size, enabling us to observe pairs of holes predominantly occupying the same rung of the ladder. We find a hole-hole binding energy of the order of the superexchange energy and, upon increased doping, we observe spatial structures in the pair distribution, indicating repulsion between bound hole pairs. By engineering a configuration in which binding is strongly enhanced, we delineate a strategy to increase the critical temperature for superconductivity.
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4
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Sous J, Gadjieva NA, Nuckolls C, Reichman DR, Millis AJ. Strongly Correlated Ladders in K-Doped p-Terphenyl Crystals. NANO LETTERS 2021; 21:9573-9579. [PMID: 34761676 DOI: 10.1021/acs.nanolett.1c03236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Potassium-doped terphenyl has recently attracted attention as a potential host for high-transition-temperature superconductivity. Here, we elucidate the many-body electronic structure of recently synthesized potassium-doped terphenyl crystals. We show that this system may be understood as a set of weakly coupled one-dimensional ladders. Depending on the strength of the interladder coupling, the system may exhibit insulating spin-gapped valence-bond solid or antiferromagnetic phases, both of which upon hole doping may give rise to superconductivity. This terphenyl-based ladder material serves as a new platform for investigating the fate of ladder phases in the presence of three-dimensional coupling as well as for novel superconductivity.
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Affiliation(s)
- John Sous
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Natalia A Gadjieva
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - David R Reichman
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Andrew J Millis
- Department of Physics, Columbia University, New York, New York 10027, United States
- Center for Computational Quantum Physics, Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, United States
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5
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Jiang HC, Devereaux TP. Superconductivity in the doped Hubbard model and its interplay with next-nearest hopping
t
′. Science 2019; 365:1424-1428. [DOI: 10.1126/science.aal5304] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/20/2019] [Indexed: 11/02/2022]
Affiliation(s)
- Hong-Chen Jiang
- Stanford Institute for Materials and Energy Sciences, SLAC and Stanford University, Menlo Park, CA 94025, USA
| | - Thomas P. Devereaux
- Stanford Institute for Materials and Energy Sciences, SLAC and Stanford University, Menlo Park, CA 94025, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA
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6
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White SR, Scalapino DJ, Kivelson SA. One Hole in the Two-Leg t-J Ladder and Adiabatic Continuity to the Noninteracting Limit. PHYSICAL REVIEW LETTERS 2015; 115:056401. [PMID: 26274429 DOI: 10.1103/physrevlett.115.056401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Indexed: 06/04/2023]
Abstract
We carry out density-matrix-renormalization group (DMRG) calculations for the problem of one doped hole in a two-leg t-J ladder. Recent studies have concluded that exotic "Mott" physics-arising from the projection onto the space of no double-occupied sites-is manifest in this model system, leading to charge localization and a new mechanism for charge modulation. In contrast, we show that there is no localization and that the charge-density modulation arises when the minimum in the quasiparticle dispersion moves away from π. Although singular changes in the quasiparticle dispersion do occur as a function of model parameters, all of the DMRG results can be qualitatively understood from a noninteracting "band-structure" perspective.
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Affiliation(s)
- S R White
- Department of Physics, University of California, Irvine, California 92697, USA, Department of Physics, University of California, Santa Barbara, California 93106, USA, and Department of Physics, Stanford University, Stanford, California 94305, USA
| | - D J Scalapino
- Department of Physics, University of California, Irvine, California 92697, USA, Department of Physics, University of California, Santa Barbara, California 93106, USA, and Department of Physics, Stanford University, Stanford, California 94305, USA
| | - S A Kivelson
- Department of Physics, University of California, Irvine, California 92697, USA, Department of Physics, University of California, Santa Barbara, California 93106, USA, and Department of Physics, Stanford University, Stanford, California 94305, USA
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7
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Bisogni V, Wohlfeld K, Nishimoto S, Monney C, Trinckauf J, Zhou K, Kraus R, Koepernik K, Sekar C, Strocov V, Büchner B, Schmitt T, van den Brink J, Geck J. Orbital control of effective dimensionality: from spin-orbital fractionalization to confinement in the anisotropic ladder system CaCu(2)O(3). PHYSICAL REVIEW LETTERS 2015; 114:096402. [PMID: 25793832 DOI: 10.1103/physrevlett.114.096402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Indexed: 06/04/2023]
Abstract
Fractionalization of an electronic quasiparticle into spin, charge, and orbital parts is a fundamental and characteristic property of interacting electrons in one dimension. However, real materials are never strictly one dimensional and the fractionalization phenomena are hard to observe. Here we studied the spin and orbital excitations of the anisotropic ladder material CaCu_{2}O_{3}, whose electronic structure is not one dimensional. Combining high-resolution resonant inelastic x-ray scattering experiments with theoretical model calculations, we show that (i) spin-orbital fractionalization occurs in CaCu_{2}O_{3} along the leg direction x through the xz orbital channel as in a 1D system, and (ii) no fractionalization is observed for the xy orbital, which extends in both leg and rung direction, contrary to a 1D system. We conclude that the directional character of the orbital hopping can select different degrees of dimensionality. Using additional model calculations, we show that spin-orbital separation is generally far more robust than the spin-charge separation. This is not only due to the already mentioned selection realized by the orbital hopping, but also due to the fact that spinons are faster than the orbitons.
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Affiliation(s)
- Valentina Bisogni
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
- Swiss Light Source, Paul Scherrer Insitute, CH-5232 Villigen PSI, Switzerland
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - Krzysztof Wohlfeld
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
- Stanford Institute for Materials and Energy Sciences, SLAC National Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA
- Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, Pasteura 5, PL-02093 Warsaw, Poland
| | | | - Claude Monney
- Swiss Light Source, Paul Scherrer Insitute, CH-5232 Villigen PSI, Switzerland
- Department of Physics, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Jan Trinckauf
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
| | - Kejin Zhou
- Swiss Light Source, Paul Scherrer Insitute, CH-5232 Villigen PSI, Switzerland
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Roberto Kraus
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
| | | | - Chinnathambi Sekar
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
- Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi-630 003, Tamilnadu, India
| | - Vladimir Strocov
- Swiss Light Source, Paul Scherrer Insitute, CH-5232 Villigen PSI, Switzerland
| | - Bernd Büchner
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
- Department of Physics, Technical University Dresden, D-1062 Dresden, Germany
| | - Thorsten Schmitt
- Swiss Light Source, Paul Scherrer Insitute, CH-5232 Villigen PSI, Switzerland
| | - Jeroen van den Brink
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
- Department of Physics, Technical University Dresden, D-1062 Dresden, Germany
| | - Jochen Geck
- IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany
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8
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Dolfi M, Bauer B, Troyer M, Ristivojevic Z. Multigrid algorithms for tensor network states. PHYSICAL REVIEW LETTERS 2012; 109:020604. [PMID: 23030148 DOI: 10.1103/physrevlett.109.020604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Indexed: 06/01/2023]
Abstract
The widely used density matrix renormalization group (DRMG) method often fails to converge in systems with multiple length scales, such as lattice discretizations of continuum models and dilute or weakly doped lattice models. The local optimization employed by DMRG to optimize the wave function is ineffective in updating large-scale features. Here we present a multigrid algorithm that solves these convergence problems by optimizing the wave function at different spatial resolutions. We demonstrate its effectiveness by simulating bosons in continuous space and study nonadiabaticity when ramping up the amplitude of an optical lattice. The algorithm can be generalized to tensor network methods and combined with the contractor renormalization group method to study dilute and weakly doped lattice models.
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Affiliation(s)
- Michele Dolfi
- Theoretische Physik, ETH Zurich, 8093 Zurich, Switzerland
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9
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Wang YF, Gong CD, Wang ZD. Tuning kinetic magnetism of strongly correlated electrons via a staggered flux. PHYSICAL REVIEW LETTERS 2008; 100:037202. [PMID: 18233031 DOI: 10.1103/physrevlett.100.037202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 10/03/2007] [Indexed: 05/25/2023]
Abstract
An interplay between kinetic process and magnetic ordering is manifested when strong correlation and electronic frustration are present: tuning a staggered flux phi from 0 to pi makes the ground state (GS) of an infinite-U Hubbard model change abruptly from a Nagaoka-type ferromagnet to a Haerter-Shastry-type antiferromagnet at a phi_(c), with both states being metallic and of kinetic origin. Intraplaquette spin correlation, as well as nonanalyticity in the GS energy, signals such a novel quantum criticality. This tunable kinetic magnetism is generic and may be experimentally realized.
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Affiliation(s)
- Yi-Fei Wang
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China
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10
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Notbohm S, Ribeiro P, Lake B, Tennant DA, Schmidt KP, Uhrig GS, Hess C, Klingeler R, Behr G, Büchner B, Reehuis M, Bewley RI, Frost CD, Manuel P, Eccleston RS. One- and two-triplon spectra of a cuprate ladder. PHYSICAL REVIEW LETTERS 2007; 98:027403. [PMID: 17358648 DOI: 10.1103/physrevlett.98.027403] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Indexed: 05/14/2023]
Abstract
We have performed inelastic neutron scattering on the near ideal spin-ladder compound La4Sr10Cu24O41 as a starting point for investigating doped ladders and their tendency toward superconductivity. A key feature was the separation of one-triplon and two-triplon scattering. Two-triplon scattering is observed quantitatively for the first time and so access is realized to the important strong magnetic quantum fluctuations. The spin gap is found to be 26.4+/-0.3 meV. The data are successfully modeled using the continuous unitary transformation method, and the exchange constants are determined by fitting to be Jleg=186 meV and Jrung=124 meV along the leg and rung, respectively; a substantial cyclic exchange of Jcyc=31 meV is confirmed.
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Affiliation(s)
- S Notbohm
- Hahn-Meitner-Institut Berlin, Berlin, Germany
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11
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Chen Y, Rice TM, Zhang FC. Rotational symmetry breaking in the ground state of sodium-doped cuprate superconductors. PHYSICAL REVIEW LETTERS 2006; 97:237004. [PMID: 17280234 DOI: 10.1103/physrevlett.97.237004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Indexed: 05/13/2023]
Abstract
We use an extended t-J model to study a single hole bound to a Na+ acceptor in Ca2-xNaxCuO2Cl2. For parameters suitable to cuprates, the ground state has a twofold degeneracy, corresponding to even (odd) reflection symmetry around the x (y) axes. The conductance pattern of the broken symmetry state is anisotropic as the tip of a tunneling microscope scans above the Cu-O-Cu bonds along the x (y) axes. This anisotropy is pronounced at lower voltages but reduced at higher voltages. Our theory agrees qualitatively with recent data of scanning tunneling microscopy showing broken local rotational symmetry.
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Affiliation(s)
- Yan Chen
- Department of Physics and Center of Theoretical and Computational Physics, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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12
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Trebst S, Schollwöck U, Troyer M, Zoller P. d-Wave resonating valence bond states of fermionic atoms in optical lattices. PHYSICAL REVIEW LETTERS 2006; 96:250402. [PMID: 16907290 DOI: 10.1103/physrevlett.96.250402] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Indexed: 05/11/2023]
Abstract
We study controlled generation and measurement of superfluid d-wave resonating valence bond (RVB) states of fermionic atoms in 2D optical lattices. Starting from loading spatial and spin patterns of atoms in optical superlattices as pure quantum states from a Fermi gas, we adiabatically transform this state to an RVB state by a change of the lattice parameters. Results of exact time-dependent numerical studies for ladders systems are presented, suggesting generation of RVB states on a time scale smaller than typical experimental decoherence times.
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Affiliation(s)
- Simon Trebst
- Theoretische Physik, Eidgenössische Technische Hochschule Zürich, CH-8093 Zürich, Switzerland
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13
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Schmid G, Troyer M. Melting of bosonic stripes. PHYSICAL REVIEW LETTERS 2004; 93:067003. [PMID: 15323656 DOI: 10.1103/physrevlett.93.067003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2003] [Indexed: 05/24/2023]
Abstract
We use quantum Monte Carlo simulations to determine the finite temperature phase diagram and to investigate the thermal and quantum melting of stripe phases in a two-dimensional hard-core boson model. At half filling and low temperatures the stripes melt at a first order transition. In the doped system, the melting transitions of the smectic phase at high temperatures and the superfluid smectic (supersolid) phase at low temperatures are either very weakly first order, or of second order with no clear indications for an intermediate nematic phase.
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Affiliation(s)
- Guido Schmid
- Theoretische Physik, Eidgenössische Technische Hochschule Zürich, CH-8093, Switzerland
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14
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Läuchli A, Poilblanc D. Spin-charge separation in two-dimensional frustrated quantum magnets. PHYSICAL REVIEW LETTERS 2004; 92:236404. [PMID: 15245179 DOI: 10.1103/physrevlett.92.236404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2003] [Indexed: 05/24/2023]
Abstract
The dynamics of a mobile hole in two-dimensional frustrated quantum magnets is investigated by exact diagonalization techniques. Our results provide evidence for spin-charge separation upon doping the kagome lattice, a prototype of a spin liquid. In contrast, in the checkerboard lattice, a symmetry broken valence bond crystal, a small quasiparticle peak is seen for some crystal momenta, a finding interpreted as a restoration of weak holon-spinon confinement.
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Affiliation(s)
- Andreas Läuchli
- Laboratoire de Physique Théorique, CNRS-UMR 5152, Université Paul Sabatier, F-31062 Toulouse, France
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15
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Poilblanc D, Scalapino DJ, Capponi S. Superconducting gap for a two-leg t-J ladder. PHYSICAL REVIEW LETTERS 2003; 91:137203. [PMID: 14525334 DOI: 10.1103/physrevlett.91.137203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2003] [Indexed: 05/24/2023]
Abstract
Single-particle diagonal and off-diagonal Green's functions of a two-leg t-J ladder at 1/8 doping are investigated by exact diagonalizations techniques. A numerically tractable expression for the superconducting gap is proposed and the frequency dependence of the real and imaginary parts of the gap are determined. The role of the low-energy gapped spin modes, whose energies are computed by a (one-step) contractor renormalization procedure, is discussed.
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Affiliation(s)
- Didier Poilblanc
- Laboratoire de Physique Théorique CNRS-UMR5152, Université Paul Sabatier, F-31062 Toulouse, France
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16
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Schollwöck U, Chakravarty S, Fjaerestad JO, Marston JB, Troyer M. Broken time-reversal symmetry in strongly correlated ladder structures. PHYSICAL REVIEW LETTERS 2003; 90:186401. [PMID: 12786029 DOI: 10.1103/physrevlett.90.186401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2002] [Indexed: 05/24/2023]
Abstract
We provide, for the first time, in a doped strongly correlated system (two-leg ladder), a controlled theoretical demonstration of the existence of a state in which long-range ordered orbital currents are arranged in a staggered pattern, coexisting with a charge density wave. The method used is the highly accurate density-matrix renormalization group technique. This brings us closer to recent proposals that this order is realized in the enigmatic pseudogap phase of the cuprate high temperature superconductors.
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Affiliation(s)
- U Schollwöck
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
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Blumberg G, Littlewood P, Gozar A, Dennis BS, Motoyama N, Eisaki H, Uchida S. Sliding density wave in Sr14Cu24O41 ladder compounds. Science 2002; 297:584-7. [PMID: 12142532 DOI: 10.1126/science.1070481] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We used transport and Raman scattering measurements to identify the insulating state of self-doped spin (1/2) two-leg ladders of Sr14Cu24O41 as a weakly pinned, sliding density wave with nonlinear conductivity and a giant dielectric response that persists to remarkably high temperatures.
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Affiliation(s)
- G Blumberg
- Bell Laboratories, Lucent Technologies, Murray Hill, NJ 07974, USA.
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Raman Spectroscopy of Magnetic Compounds with Strong Electron-Correlation. SPRINGER SERIES IN SOLID-STATE SCIENCES 2000. [DOI: 10.1007/978-3-662-04143-7_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Fabrizio M. Superconductivity from doping a spin-liquid insulator: A simple one-dimensional example. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:10054-10060. [PMID: 9984743 DOI: 10.1103/physrevb.54.10054] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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