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Yu Y, Iskakov S, Gull E, Held K, Krien F. Unambiguous Fluctuation Decomposition of the Self-Energy: Pseudogap Physics beyond Spin Fluctuations. PHYSICAL REVIEW LETTERS 2024; 132:216501. [PMID: 38856250 DOI: 10.1103/physrevlett.132.216501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 04/15/2024] [Indexed: 06/11/2024]
Abstract
Correlated electron systems may give rise to multiple effective interactions whose combined impact on quasiparticle properties can be difficult to disentangle. We introduce an unambiguous decomposition of the electronic self-energy which allows us to quantify the contributions of various effective interactions simultaneously. We use this tool to revisit the hole-doped Hubbard model within the dynamical cluster approximation, where commonly spin fluctuations are considered to be the origin of the pseudogap. While our fluctuation decomposition confirms that spin fluctuations indeed suppress antinodal electronic spectral weight, we show that they alone cannot capture the pseudogap self-energy quantitatively. Nonlocal multiboson Feynman diagrams yield substantial contributions and are needed for a quantitative description of the pseudogap.
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Affiliation(s)
- Yang Yu
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Sergei Iskakov
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Emanuel Gull
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Karsten Held
- Institute for Solid State Physics, TU Wien, 1040 Vienna, Austria
| | - Friedrich Krien
- Institute for Solid State Physics, TU Wien, 1040 Vienna, Austria
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2
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Differentiated roles of Lifshitz transition on thermodynamics and superconductivity in La 2-xSr xCuO 4. Proc Natl Acad Sci U S A 2022; 119:e2204630119. [PMID: 35914123 PMCID: PMC9371668 DOI: 10.1073/pnas.2204630119] [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: 02/03/2023] Open
Abstract
The effect of Lifshitz transition on thermodynamics and superconductivity in hole-doped cuprates has been heavily debated but remains an open question. In particular, an observed peak of electronic specific heat is proposed to originate from fluctuations of a putative quantum critical point p* (e.g., the termination of pseudogap at zero temperature), which is close to but distinguishable from the Lifshitz transition in overdoped La-based cuprates where the Fermi surface transforms from hole-like to electron-like. Here we report an in situ angle-resolved photoemission spectroscopy study of three-dimensional Fermi surfaces in La2-xSrxCuO4 thin films (x = 0.06 to 0.35). With accurate kz dispersion quantification, the said Lifshitz transition is determined to happen within a finite range around x = 0.21. Normal state electronic specific heat, calculated from spectroscopy-derived band parameters, reveals a doping-dependent profile with a maximum at x = 0.21 that agrees with previous thermodynamic microcalorimetry measurements. The account of the specific heat maximum by underlying band structures excludes the need for additionally dominant contribution from the quantum fluctuations at p*. A d-wave superconducting gap smoothly across the Lifshitz transition demonstrates the insensitivity of superconductivity to the dramatic density of states enhancement.
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3
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Robinson NJ, Johnson PD, Rice TM, Tsvelik AM. Anomalies in the pseudogap phase of the cuprates: competing ground states and the role of umklapp scattering. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:126501. [PMID: 31300626 DOI: 10.1088/1361-6633/ab31ed] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Over the past two decades, advances in computational algorithms have revealed a curious property of the two-dimensional Hubbard model (and related theories) with hole doping: the presence of close-in-energy competing ground states that display very different physical properties. On the one hand, there is a complicated state exhibiting intertwined spin, charge, and pair density wave orders. We call this 'type A'. On the other hand, there is a uniform d-wave superconducting state that we denote as 'type B'. We advocate, with the support of both microscopic theoretical calculations and experimental data, dividing the high-temperature cuprate superconductors into two corresponding families, whose properties reflect either the type A or type B ground states at low temperatures. We review the anomalous properties of the pseudogap phase that led us to this picture, and present a modern perspective on the role that umklapp scattering plays in these phenomena in the type B materials. This reflects a consistent framework that has emerged over the last decade, in which Mott correlations at weak coupling drive the formation of the pseudogap. We discuss this development, recent theory and experiments, and open issues.
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Affiliation(s)
- Neil J Robinson
- Institute for Theoretical Physics, University of Amsterdam, Science Park 904, Postbus 94485, 1098 XH Amsterdam, The Netherlands
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Abstract
We compute the electronic Green's function of the topologically ordered Higgs phase of a SU(2) gauge theory of fluctuating antiferromagnetism on the square lattice. The results are compared with cluster extensions of dynamical mean field theory, and quantum Monte Carlo calculations, on the pseudogap phase of the strongly interacting hole-doped Hubbard model. Good agreement is found in the momentum, frequency, hopping, and doping dependencies of the spectral function and electronic self-energy. We show that lines of (approximate) zeros of the zero-frequency electronic Green's function are signs of the underlying topological order of the gauge theory and describe how these lines of zeros appear in our theory of the Hubbard model. We also derive a modified, nonperturbative version of the Luttinger theorem that holds in the Higgs phase.
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Kohno M. Characteristics of the Mott transition and electronic states of high-temperature cuprate superconductors from the perspective of the Hubbard model. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:042501. [PMID: 29300706 DOI: 10.1088/1361-6633/aaa53d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A fundamental issue of the Mott transition is how electrons behaving as single particles carrying spin and charge in a metal change into those exhibiting separated spin and charge excitations (low-energy spin excitation and high-energy charge excitation) in a Mott insulator. This issue has attracted considerable attention particularly in relation to high-temperature cuprate superconductors, which exhibit electronic states near the Mott transition that are difficult to explain in conventional pictures. Here, from a new viewpoint of the Mott transition based on analyses of the Hubbard model, we review anomalous features observed in high-temperature cuprate superconductors near the Mott transition.
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Affiliation(s)
- Masanori Kohno
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba 305-0044, Japan
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6
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Bragança H, Sakai S, Aguiar MCO, Civelli M. Correlation-Driven Lifshitz Transition at the Emergence of the Pseudogap Phase in the Two-Dimensional Hubbard Model. PHYSICAL REVIEW LETTERS 2018; 120:067002. [PMID: 29481286 DOI: 10.1103/physrevlett.120.067002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Indexed: 06/08/2023]
Abstract
We study the relationship between the pseudogap and Fermi-surface topology in the two-dimensional Hubbard model by means of the cellular dynamical mean-field theory. We find two possible mean-field metallic solutions on a broad range of interactions, doping, and frustration: a conventional renormalized metal and an unconventional pseudogap metal. At half filling, the conventional metal is more stable and displays an interaction-driven Mott metal-insulator transition. However, for large interactions and small doping, a region that is relevant for cuprates, the pseudogap phase becomes the ground state. By increasing doping, we show that a first-order transition from the pseudogap to the conventional metal is tied to a change of the Fermi surface from hole- to electronlike, unveiling a correlation-driven mechanism for a Lifshitz transition. This explains the puzzling link between the pseudogap phase and Fermi surface topology that has been pointed out in recent experiments.
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Affiliation(s)
- Helena Bragança
- Departamento de Física, Universidade Federal de Minas Gerais, C. P. 702, 30123-970 Belo Horizonte, Minas Gerais, Brazil
- Laboratoire de Physique des Solides, CNRS UMR 8502, Univ. Paris-Sud, Université Paris-Saclay F-91405 Orsay Cedex, France
| | - Shiro Sakai
- Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan
| | - M C O Aguiar
- Departamento de Física, Universidade Federal de Minas Gerais, C. P. 702, 30123-970 Belo Horizonte, Minas Gerais, Brazil
| | - Marcello Civelli
- Laboratoire de Physique des Solides, CNRS UMR 8502, Univ. Paris-Sud, Université Paris-Saclay F-91405 Orsay Cedex, France
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7
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Cilento F, Manzoni G, Sterzi A, Peli S, Ronchi A, Crepaldi A, Boschini F, Cacho C, Chapman R, Springate E, Eisaki H, Greven M, Berciu M, Kemper AF, Damascelli A, Capone M, Giannetti C, Parmigiani F. Dynamics of correlation-frozen antinodal quasiparticles in superconducting cuprates. SCIENCE ADVANCES 2018; 4:eaar1998. [PMID: 29507885 PMCID: PMC5834002 DOI: 10.1126/sciadv.aar1998] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 01/22/2018] [Indexed: 05/27/2023]
Abstract
Many puzzling properties of high-critical temperature (Tc) superconducting (HTSC) copper oxides have deep roots in the nature of the antinodal quasiparticles, the elementary excitations with wave vector parallel to the Cu-O bonds. These electronic states are most affected by the onset of antiferromagnetic correlations and charge instabilities, and they host the maximum of the anisotropic superconducting gap and pseudogap. We use time-resolved extreme-ultraviolet photoemission with proper photon energy (18 eV) and time resolution (50 fs) to disclose the ultrafast dynamics of the antinodal states in a prototypical HTSC cuprate. After photoinducing a nonthermal charge redistribution within the Cu and O orbitals, we reveal a dramatic momentum-space differentiation of the transient electron dynamics. Whereas the nodal quasiparticle distribution is heated up as in a conventional metal, new quasiparticle states transiently emerge at the antinodes, similarly to what is expected for a photoexcited Mott insulator, where the frozen charges can be released by an impulsive excitation. This transient antinodal metallicity is mapped into the dynamics of the O-2p bands, thus directly demonstrating the intertwining between the low- and high-energy scales that is typical of correlated materials. Our results suggest that the correlation-driven freezing of the electrons moving along the Cu-O bonds, analogous to the Mott localization mechanism, constitutes the starting point for any model of high-Tc superconductivity and other exotic phases of HTSC cuprates.
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Affiliation(s)
| | - Giulia Manzoni
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza, Italy
- Dipartimento di Fisica, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Andrea Sterzi
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza, Italy
- Dipartimento di Fisica, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Simone Peli
- Interdisciplinary Laboratories for Advanced Materials Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - Andrea Ronchi
- Interdisciplinary Laboratories for Advanced Materials Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
- Department of Physics and Astronomy, Katholieke Universiteit Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
| | - Alberto Crepaldi
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Fabio Boschini
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Cephise Cacho
- CLF-Artemis@Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, UK
| | - Richard Chapman
- CLF-Artemis@Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, UK
| | - Emma Springate
- CLF-Artemis@Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, UK
| | - Hiroshi Eisaki
- Nanoelectronics Research Institute, National Institute of Advanced Industrial Science Technology, Tsukuba, Ibaraki 305-8568, Japan
| | - Martin Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mona Berciu
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Alexander F. Kemper
- Department of Physics, North Carolina State University, Raleigh, NC 27695, USA
| | - Andrea Damascelli
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Massimo Capone
- Scuola Internazionale Superiore di Studi Avanzati (SISSA) and Consiglio Nazionale delle Ricerche–Istituto Officina dei Materiali (CNR-IOM) Democritos National Simulation Center, Via Bonomea 265, 34136 Trieste, Italy
| | - Claudio Giannetti
- Interdisciplinary Laboratories for Advanced Materials Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - Fulvio Parmigiani
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza, Italy
- Dipartimento di Fisica, Università degli Studi di Trieste, 34127 Trieste, Italy
- International Faculty, University of Cologne, Albertus-Magnus-Platz, 50923 Cologne, Germany
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8
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Ayral T, Vučičević J, Parcollet O. Fierz Convergence Criterion: A Controlled Approach to Strongly Interacting Systems with Small Embedded Clusters. PHYSICAL REVIEW LETTERS 2017; 119:166401. [PMID: 29099214 DOI: 10.1103/physrevlett.119.166401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Indexed: 06/07/2023]
Abstract
We present an embedded-cluster method, based on the triply irreducible local expansion formalism. It turns the Fierz ambiguity, inherent to approaches based on a bosonic decoupling of local fermionic interactions, into a convergence criterion. It is based on the approximation of the three-leg vertex by a coarse-grained vertex computed from a self-consistently determined cluster impurity model. The computed self-energies are, by construction, continuous functions of momentum. We show that, in three interaction and doping regimes of the two-dimensional Hubbard model, self-energies obtained with clusters of size four only are very close to numerically exact benchmark results. We show that the Fierz parameter, which parametrizes the freedom in the Hubbard-Stratonovich decoupling, can be used as a quality control parameter. By contrast, the GW+extended dynamical mean field theory approximation with four cluster sites is shown to yield good results only in the weak-coupling regime and for a particular decoupling. Finally, we show that the vertex has spatially nonlocal components only at low Matsubara frequencies.
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Affiliation(s)
- Thomas Ayral
- Physics and Astronomy Department, Rutgers University, Piscataway, New Jersey 08854, USA
- Institut de Physique Théorique (IPhT), CEA, CNRS, UMR 3681, 91191 Gif-sur-Yvette, France
| | - Jaksa Vučičević
- Institut de Physique Théorique (IPhT), CEA, CNRS, UMR 3681, 91191 Gif-sur-Yvette, France
- Scientific Computing Laboratory, Center for the Study of Complex Systems, Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia
| | - Olivier Parcollet
- Institut de Physique Théorique (IPhT), CEA, CNRS, UMR 3681, 91191 Gif-sur-Yvette, France
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9
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Loret B, Sakai S, Gallais Y, Cazayous M, Méasson MA, Forget A, Colson D, Civelli M, Sacuto A. Unconventional High-Energy-State Contribution to the Cooper Pairing in the Underdoped Copper-Oxide Superconductor HgBa_{2}Ca_{2}Cu_{3}O_{8+δ}. PHYSICAL REVIEW LETTERS 2016; 116:197001. [PMID: 27232035 DOI: 10.1103/physrevlett.116.197001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Indexed: 06/05/2023]
Abstract
We study the temperature-dependent electronic B_{1g} Raman response of a slightly underdoped single crystal HgBa_{2}Ca_{2}Cu_{3}O_{8+δ} with a superconducting critical temperature T_{c}=122 K. Our main finding is that the superconducting pair-breaking peak is associated with a dip on its higher-energy side, disappearing together at T_{c}. This result reveals a key aspect of the unconventional pairing mechanism: spectral weight lost in the dip is transferred to the pair-breaking peak at lower energies. This conclusion is supported by cellular dynamical mean-field theory on the Hubbard model, which is able to reproduce all the main features of the B_{1g} Raman response and explain the peak-dip behavior in terms of a nontrivial relationship between the superconducting gap and the pseudogap.
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Affiliation(s)
- B Loret
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - S Sakai
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Y Gallais
- 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
| | - M-A Méasson
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - A Forget
- Service de Physique de l'État Condensé, DSM/IRAMIS/SPEC (UMR 3680 CNRS), CEA Saclay 91191 Gif sur Yvette cedex France
| | - D Colson
- Service de Physique de l'État Condensé, DSM/IRAMIS/SPEC (UMR 3680 CNRS), CEA Saclay 91191 Gif sur Yvette cedex France
| | - M Civelli
- Laboratoire de Physique des Solides, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - A Sacuto
- Laboratoire Matériaux et Phénomènes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
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10
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Hallmarks of the Mott-metal crossover in the hole-doped pseudospin-1/2 Mott insulator Sr2IrO4. Nat Commun 2016; 7:11367. [PMID: 27102065 PMCID: PMC4844699 DOI: 10.1038/ncomms11367] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 03/20/2016] [Indexed: 11/12/2022] Open
Abstract
The physics of doped Mott insulators remains controversial after decades of active research, hindered by the interplay among competing orders and fluctuations. It is thus highly desired to distinguish the intrinsic characters of the Mott-metal crossover from those of other origins. Here we investigate the evolution of electronic structure and dynamics of the hole-doped pseudospin-1/2 Mott insulator Sr2IrO4. The effective hole doping is achieved by replacing Ir with Rh atoms, with the chemical potential immediately jumping to or near the top of the lower Hubbard band. The doped iridates exhibit multiple iconic low-energy features previously observed in doped cuprates—pseudogaps, Fermi arcs and marginal-Fermi-liquid-like electronic scattering rates. We suggest these signatures are most likely an integral part of the material's proximity to the Mott state, rather than from many of the most claimed mechanisms, including preformed electron pairing, quantum criticality or density-wave formation. The physics of Mott insulators is obscured by the interplay between competing orders and fluctuations. Here, the authors track the evolution of the electronic structure of Mott insulator strontium iridate as the iridium atoms are replaced by rhodium, providing insight into this exotic state of matter.
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11
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Sakai S, Civelli M, Imada M. Hidden Fermionic Excitation Boosting High-Temperature Superconductivity in Cuprates. PHYSICAL REVIEW LETTERS 2016; 116:057003. [PMID: 26894730 DOI: 10.1103/physrevlett.116.057003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Indexed: 06/05/2023]
Abstract
The dynamics of a microscopic cuprate model, namely, the two-dimensional Hubbard model, is studied with a cluster extension of the dynamical mean-field theory. We find a nontrivial structure of the frequency-dependent self-energies, which describes an unprecedented interplay between the pseudogap and superconductivity. We show that these properties are well described by quasiparticles hybridizing with (hidden) fermionic excitations, emergent from the strong electronic correlations. The hidden fermion enhances superconductivity via a mechanism distinct from a conventional boson-mediated pairing, and originates the normal-state pseudogap. Though the hidden fermion is elusive in experiments, it can solve many experimental puzzles.
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Affiliation(s)
- Shiro Sakai
- Department of Applied Physics, University of Tokyo, Hongo, Tokyo 113-8656, Japan
- Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan
| | - Marcello Civelli
- Laboratoire de Physique des Solides, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Masatoshi Imada
- Department of Applied Physics, University of Tokyo, Hongo, Tokyo 113-8656, Japan
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12
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Merino J, Gunnarsson O, Kotliar G. Self-energy behavior away from the Fermi surface in doped Mott insulators. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:045501. [PMID: 26742570 DOI: 10.1088/0953-8984/28/4/045501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We analyze self-energies of electrons away from the Fermi surface in doped Mott insulators using the dynamical cluster approximation to the Hubbard model. For large onsite repulsion, U, and hole doping, the magnitude of the self-energy for imaginary frequencies at the top of the band ([Formula: see text]) is enhanced with respect to the self-energy magnitude at the bottom of the band ([Formula: see text]). The self-energy behavior at these two [Formula: see text]-points is switched for electron doping. Although the hybridization is much larger for (0, 0) than for [Formula: see text], we demonstrate that this is not the origin of this difference. Isolated clusters under a downward shift of the chemical potential, [Formula: see text], at half-filling reproduce the overall self-energy behavior at (0, 0) and [Formula: see text] found in low hole doped embedded clusters. This happens although there is no change in the electronic structure of the isolated clusters. Our analysis shows that a downward shift of the chemical potential which weakly hole dopes the Mott insulator can lead to a large enhancement of the [Formula: see text] self-energy for imaginary frequencies which is not associated with electronic correlation effects, even in embedded clusters. Interpretations of the strength of electronic correlations based on self-energies for imaginary frequencies are, in general, misleading for states away from the Fermi surface.
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Affiliation(s)
- J Merino
- Departamento de Física Teórica de la Materia Condensada, Condensed Matter Physics Center (IFIMAC) and Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, Madrid 28049, Spain
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13
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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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14
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Sakai S, Blanc S, Civelli M, Gallais Y, Cazayous M, Méasson MA, Wen JS, Xu ZJ, Gu GD, Sangiovanni G, Motome Y, Held K, Sacuto A, Georges A, Imada M. Raman-scattering measurements and theory of the energy-momentum spectrum for underdoped Bi2Sr2CaCuO(8+δ) superconductors: evidence of an s-wave structure for the pseudogap. PHYSICAL REVIEW LETTERS 2013; 111:107001. [PMID: 25166695 DOI: 10.1103/physrevlett.111.107001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Indexed: 06/03/2023]
Abstract
We reveal the full energy-momentum structure of the pseudogap of underdoped high-Tc cuprate superconductors. Our combined theoretical and experimental analysis explains the spectral-weight suppression observed in the B2g Raman response at finite energies in terms of a pseudogap appearing in the single-electron excitation spectra above the Fermi level in the nodal direction of momentum space. This result suggests an s-wave pseudogap (which never closes in the energy-momentum space), distinct from the d-wave superconducting gap. Recent tunneling and photoemission experiments on underdoped cuprates also find a natural explanation within the s-wave pseudogap scenario.
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Affiliation(s)
- S Sakai
- Centre de Physique Théorique, École Polytechnique, CNRS, 91128 Palaiseau, France and Department of Applied Physics, University of Tokyo, Hongo, Tokyo 113-8656, Japan and JST-CREST, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - S Blanc
- Laboratoire Matériaux et Phénomnes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M Civelli
- Laboratoire de Physique des Solides, Université Paris-Sud, CNRS, UMR 8502, F-91405 Orsay Cedex, France
| | - Y Gallais
- Laboratoire Matériaux et Phénomnes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M Cazayous
- Laboratoire Matériaux et Phénomnes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M-A Méasson
- Laboratoire Matériaux et Phénomnes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - J S Wen
- Matter Physics and Materials Science, Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
| | - Z J Xu
- 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
| | - G Sangiovanni
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany and Institute for Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
| | - Y Motome
- Department of Applied Physics, University of Tokyo, Hongo, Tokyo 113-8656, Japan
| | - K Held
- Institute for Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
| | - A Sacuto
- Laboratoire Matériaux et Phénomnes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - A Georges
- Centre de Physique Théorique, École Polytechnique, CNRS, 91128 Palaiseau, France and JST-CREST, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan and Collège de France, 11 Place Marcelin Berthelot, 75005 Paris, France and DPMC, Université de Genève, 24 Quai Ernest Ansermet, CH-1211 Genève, Suisse
| | - M Imada
- Department of Applied Physics, University of Tokyo, Hongo, Tokyo 113-8656, Japan and JST-CREST, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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16
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Gull E, Parcollet O, Millis AJ. Superconductivity and the pseudogap in the two-dimensional Hubbard model. PHYSICAL REVIEW LETTERS 2013; 110:216405. [PMID: 23745902 DOI: 10.1103/physrevlett.110.216405] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Indexed: 06/02/2023]
Abstract
Recently developed numerical methods have enabled the explicit construction of the superconducting state of the Hubbard model of strongly correlated electrons in parameter regimes where the model also exhibits a pseudogap and a Mott insulating phase. d(x(2)-y(2)) symmetry superconductivity is found to occur in proximity to the Mott insulator, but separated from it by a pseudogapped nonsuperconducting phase. The superconducting transition temperature and order parameter amplitude are found to be maximal at the onset of the normal-state pseudogap. The emergence of superconductivity from the normal state pseudogap leads to a decrease in the excitation gap. All of these features are consistent with the observed behavior of the copper-oxide superconductors.
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Affiliation(s)
- Emanuel Gull
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
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17
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Merino J, Gunnarsson O. Origin of the pseudogap in cuprate superconductors from quantum cluster theories. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:052201. [PMID: 23264461 DOI: 10.1088/0953-8984/25/5/052201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We analyze the origin of the pseudogap present in cuprate superconductors. We elucidate the mechanism of pseudogap formation close to the Mott localization within the dynamical cluster approach (DCA) to the Hubbard model. As the Coulomb interaction is increased, cluster-bath Kondo states are destroyed and a nondegenerate bound cluster state is formed, leading to a pseudogap. This occurs first at the antinodal point due to its weaker coupling to the bath, explaining the momentum dependence of the pseudogap. We find that the character of the pseudogap is related to breaking d-wave pairs.
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Affiliation(s)
- J Merino
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049, Spain.
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18
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Raczkowski M, Assaad FF. Dimensional-crossover-driven Mott transition in the frustrated Hubbard model. PHYSICAL REVIEW LETTERS 2012; 109:126404. [PMID: 23005966 DOI: 10.1103/physrevlett.109.126404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Indexed: 06/01/2023]
Abstract
We study the Mott transition in a frustrated Hubbard model with next-nearest neighbor hopping at half-filling. The interplay between interaction, dimensionality, and geometric frustration closes the one-dimensional Mott gap and gives rise to a metallic phase with Fermi surface pockets. We argue that they emerge as a consequence of remnant one-dimensional umklapp scattering at the momenta with vanishing interchain hopping matrix elements. In this pseudogap phase, enhanced d-wave pairing correlations are driven by antiferromagnetic fluctuations. Within the adopted cluster dynamical mean-field theory on the 8 × 2 cluster and down to our lowest temperatures, the transition from one to two dimensions is continuous.
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Affiliation(s)
- Marcin Raczkowski
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Germany
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19
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Laad MS, Koley S, Taraphder A. Quantum critical phase and Lifshitz transition in an extended periodic Anderson model. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:232201. [PMID: 22589244 DOI: 10.1088/0953-8984/24/23/232201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We study the quantum phase transition in f-electron systems as a quantum Lifshitz transition driven by selective-Mott localization in a realistic extended Anderson lattice model. Using dynamical mean-field theory (DMFT), we find that a quantum critical phase with anomalous ω/T scaling separates a heavy Landau-Fermi liquid from ordered phase(s). This non-Fermi liquid state arises from a lattice orthogonality catastrophe originating from orbital-selective Mott localization. Fermi surface reconstruction occurs via the interplay between and penetration of the Green function zeros to the poles, leading to violation of Luttinger's theorem in the strange metal. We show how this naturally leads to scale-invariant responses in transport. Thus, our work represents a specific DMFT realization of the hidden-FL and FL* theories, and holds promise for the study of 'strange' metal phases in quantum matter.
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Affiliation(s)
- M S Laad
- Institut für Theoretische Physik, RWTH Aachen University, Aachen 52056, Germany
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20
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Liebsch A, Ishida H. Temperature and bath size in exact diagonalization dynamical mean field theory. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:053201. [PMID: 22156113 DOI: 10.1088/0953-8984/24/5/053201] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Dynamical mean field theory (DMFT), combined with finite-temperature exact diagonalization, is one of the methods used to describe electronic properties of strongly correlated materials. Because of the rapid growth of the Hilbert space, the size of the finite bath used to represent the infinite lattice is severely limited. In view of the increasing interest in the effect of multi-orbital and multi-site Coulomb correlations in transition metal oxides, high-T(c) cuprates, iron-based pnictides, organic crystals, etc, it is appropriate to explore the range of temperatures and bath sizes in which exact diagonalization provides accurate results for various system properties. On the one hand, the bath must be large enough to achieve a sufficiently dense level spacing, so that useful spectral information can be derived, especially close to the Fermi level. On the other hand, for an adequate projection of the lattice Green's function onto a finite bath, the choice of the temperature is crucial. The role of these two key ingredients in exact diagonalization DMFT is discussed for a wide variety of systems in order to establish the domain of applicability of this approach. Three criteria are used to illustrate the accuracy of the results: (i) the convergence of the self-energy with the bath size, (ii) the quality of the discretization of the bath Green's function, and (iii) comparisons with complementary results obtained via continuous-time quantum Monte Carlo DMFT. The materials comprise a variety of three-orbital and five-orbital systems, as well as single-band Hubbard models for two-dimensional triangular, square and honeycomb lattices, where non-local Coulomb correlations are important. The main conclusion from these examples is that a larger number of correlated orbitals or sites requires a smaller number of bath levels. Down to temperatures of 5-10 meV (for typical bandwidths W ≈ 2 eV) two bath levels per correlated impurity orbital or site are usually adequate.
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Affiliation(s)
- Ansgar Liebsch
- Peter Grünberg Institute and Institute of Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany.
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21
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Yoshimatsu K, Okabe T, Kumigashira H, Okamoto S, Aizaki S, Fujimori A, Oshima M. Dimensional-crossover-driven metal-insulator transition in SrVO3 ultrathin films. PHYSICAL REVIEW LETTERS 2010; 104:147601. [PMID: 20481962 DOI: 10.1103/physrevlett.104.147601] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Indexed: 05/29/2023]
Abstract
We have investigated the changes occurring in the electronic structure of digitally controlled SrVO(3) ultrathin films across the metal-insulator transition (MIT) by the film thickness using in situ photoemission spectroscopy. With decreasing film thickness, a pseudogap is formed at E(F) through spectral weight transfer from the coherent part to the incoherent part. The pseudogap finally evolves into an energy gap that is indicative of the MIT in a SrVO(3) ultrathin film. The observed spectral behavior is reproduced by layer dynamical-mean-field-theory calculations, and it indicates that the observed MIT is caused by the reduction in the bandwidth due to the dimensional crossover.
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Affiliation(s)
- K Yoshimatsu
- Department of Applied Chemistry, University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
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22
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Sakai S, Motome Y, Imada M. Evolution of electronic structure of doped Mott insulators: reconstruction of poles and zeros of Green's function. PHYSICAL REVIEW LETTERS 2009; 102:056404. [PMID: 19257530 DOI: 10.1103/physrevlett.102.056404] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Indexed: 05/27/2023]
Abstract
We study the evolution of metals from Mott insulators in the carrier-doped 2D Hubbard model using a cluster extension of the dynamical mean-field theory. While the conventional metal is simply characterized by the Fermi surface (pole of the Green function G), interference of the zero surfaces of G with the pole surfaces becomes crucial in the doped Mott insulators. Mutually interfering pole and zero surfaces are dramatically transferred over the Mott gap, when lightly doped holes synergetically loosen the doublon-holon binding. The heart of the Mott physics such as the pseudogap, hole pockets, Fermi arcs, in-gap states, Lifshitz transitions, and non-Fermi liquids appears as natural consequences of this global interference in the frequency space.
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Affiliation(s)
- Shiro Sakai
- Department of Applied Physics, University of Tokyo, Hongo, Tokyo 113-8656, Japan
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23
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Kohsaka Y, Taylor C, Wahl P, Schmidt A, Lee J, Fujita K, Alldredge JW, McElroy K, Lee J, Eisaki H, Uchida S, Lee DH, Davis JC. How Cooper pairs vanish approaching the Mott insulator in Bi2Sr2CaCu2O8+delta. Nature 2008; 454:1072-8. [PMID: 18756248 DOI: 10.1038/nature07243] [Citation(s) in RCA: 295] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 07/03/2008] [Indexed: 11/10/2022]
Abstract
The antiferromagnetic ground state of copper oxide Mott insulators is achieved by localizing an electron at each copper atom in real space (r-space). Removing a small fraction of these electrons (hole doping) transforms this system into a superconducting fluid of delocalized Cooper pairs in momentum space (k-space). During this transformation, two distinctive classes of electronic excitations appear. At high energies, the mysterious 'pseudogap' excitations are found, whereas, at lower energies, Bogoliubov quasi-particles-the excitations resulting from the breaking of Cooper pairs-should exist. To explore this transformation, and to identify the two excitation types, we have imaged the electronic structure of Bi(2)Sr(2)CaCu(2)O(8+delta) in r-space and k-space simultaneously. We find that although the low-energy excitations are indeed Bogoliubov quasi-particles, they occupy only a restricted region of k-space that shrinks rapidly with diminishing hole density. Concomitantly, spectral weight is transferred to higher energy r-space states that lack the characteristics of excitations from delocalized Cooper pairs. Instead, these states break translational and rotational symmetries locally at the atomic scale in an energy-independent way. We demonstrate that these unusual r-space excitations are, in fact, the pseudogap states. Thus, as the Mott insulating state is approached by decreasing the hole density, the delocalized Cooper pairs vanish from k-space, to be replaced by locally translational- and rotational-symmetry-breaking pseudogap states in r-space.
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Affiliation(s)
- Y Kohsaka
- LASSP, Department of Physics, Cornell University, Ithaca, New York 14853, USA
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Civelli M, Capone M, Georges A, Haule K, Parcollet O, Stanescu TD, Kotliar G. Nodal-antinodal dichotomy and the two gaps of a superconducting doped Mott insulator. PHYSICAL REVIEW LETTERS 2008; 100:046402. [PMID: 18352310 DOI: 10.1103/physrevlett.100.046402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2007] [Indexed: 05/26/2023]
Abstract
We study the superconducting state of the hole-doped two-dimensional Hubbard model using cellular dynamical mean-field theory, with the Lanczos method as impurity solver. In the underdoped regime, we find a natural decomposition of the one-particle (photoemission) energy gap into two components. The gap in the nodal regions, stemming from the anomalous self-energy, decreases with decreasing doping. The antinodal gap has an additional contribution from the normal component of the self-energy, inherited from the normal-state pseudogap, and it increases as the Mott insulating phase is approached.
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Affiliation(s)
- M Civelli
- Theory Group, Institut Laue Langevin, Grenoble, France
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25
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Costi TA, Liebsch A. Quantum phase transition in the two-band hubbard model. PHYSICAL REVIEW LETTERS 2007; 99:236404. [PMID: 18233389 DOI: 10.1103/physrevlett.99.236404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Indexed: 05/25/2023]
Abstract
The interaction between itinerant and Mott localized electronic states in strongly correlated materials is studied within dynamical mean field theory in combination with the numerical renormalization group method. A novel nonmagnetic zero temperature quantum phase transition is found in the bad-metallic orbital-selective Mott phase of the two-band Hubbard model, for values of the Hund's exchange which are relevant to typical transition metal oxides.
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Affiliation(s)
- T A Costi
- Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany
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26
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Merino J. Nonlocal Coulomb correlations in metals close to a charge order insulator transition. PHYSICAL REVIEW LETTERS 2007; 99:036404. [PMID: 17678302 DOI: 10.1103/physrevlett.99.036404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Indexed: 05/16/2023]
Abstract
The charge ordering transition induced by the nearest-neighbor Coulomb repulsion V in the 1/4-filled extended Hubbard model is investigated using cellular dynamical mean-field theory. We find a transition to a strongly renormalized charge ordered Fermi liquid at V(CO) and a metal-to-insulator transition at V(MI)>V(CO). Short range antiferromagnetism occurs concomitantly with the CO transition. Approaching the charge ordered insulator, V approximately <V(MI), the Fermi surface deforms and the scattering rate of electrons develops momentum dependence on the Fermi surface.
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Affiliation(s)
- Jaime Merino
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid 28049, Spain
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27
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Dao TL, Georges A, Dalibard J, Salomon C, Carusotto I. Measuring the one-particle excitations of ultracold fermionic atoms by stimulated Raman spectroscopy. PHYSICAL REVIEW LETTERS 2007; 98:240402. [PMID: 17677945 DOI: 10.1103/physrevlett.98.240402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Indexed: 05/16/2023]
Abstract
We propose a Raman spectroscopy technique which is able to probe the one-particle Green function, the Fermi surface, and the quasiparticles of a gas of strongly interacting ultracold atoms. We give quantitative examples of experimentally accessible spectra. The efficiency of the method is validated by means of simulated images for the case of a usual Fermi liquid as well as for more exotic states: specific signatures of, e.g., a d-wave pseudogap are clearly visible.
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Affiliation(s)
- Tung-Lam Dao
- Centre de Physique Théorique, CNRS, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex, France
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28
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Konik RM, Rice TM, Tsvelik AM. Doped spin liquid: Luttinger sum rule and low temperature order. PHYSICAL REVIEW LETTERS 2006; 96:086407. [PMID: 16606208 DOI: 10.1103/physrevlett.96.086407] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Indexed: 05/08/2023]
Abstract
We analyze a model of two-leg Hubbard ladders weakly coupled by interladder tunneling. At half filling a semimetallic state with small Fermi pockets is induced beyond a threshold tunneling strength. The sign changes in the single electron Green's function relevant for the Luttinger sum rule now take place at surfaces with both zeros and infinities with important consequences for the interpretation of angle-resolved photoemission spectroscopy experiments. Residual interactions between electron and holelike quasiparticles cause a transition to long range order at low temperatures. The theory can be extended to small doping leading to superconducting order.
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Affiliation(s)
- R M Konik
- Department of Physics, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
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