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Gozlinski T, Henn M, Wolf T, Le Tacon M, Schmalian J, Wulfhekel W. Bosonic excitation spectra of superconductingBi2Sr2CaCu2O8+δandYBa2Cu3O6+xextracted from scanning tunneling spectra. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:175601. [PMID: 38194720 DOI: 10.1088/1361-648x/ad1ca8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 01/09/2024] [Indexed: 01/11/2024]
Abstract
A detailed interpretation of scanning tunneling spectra obtained on unconventional superconductors enables one to gain information on the pairing boson. Decisive for this approach are inelastic tunneling events. Due to the lack of momentum conservation in tunneling from or to the sharp tip, those are enhanced in the geometry of a scanning tunneling microscope compared to planar tunnel junctions. This work extends the method of obtaining the bosonic excitation spectrum by deconvolution from tunneling spectra to nodald-wave superconductors. In particular, scanning tunneling spectra of slightly underdopedBi2Sr2CaCu2O8+δwith aTcof 82 K and optimally dopedYBa2Cu3O6+xwith aTcof 92 K reveal a resonance mode in their bosonic excitation spectrum atΩres≈63 meVandΩres≈61 meVrespectively. In both cases, the overall shape of the bosonic excitation spectrum is indicative of predominant spin scattering with a resonant mode atΩres<2Δand overdamped spin fluctuations for energies larger than 2Δ. To perform the deconvolution of the experimental data, we implemented an efficient iterative algorithm that significantly enhances the reliability of our analysis.
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Affiliation(s)
- Thomas Gozlinski
- Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Mirjam Henn
- Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Thomas Wolf
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Matthieu Le Tacon
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Jörg Schmalian
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
- Institute for Theory of Condensed Matter, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Wulf Wulfhekel
- Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
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2
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Yan H, Bok JM, He J, Zhang W, Gao Q, Luo X, Cai Y, Peng Y, Meng J, Li C, Chen H, Song C, Yin C, Miao T, Chen Y, Gu G, Lin C, Zhang F, Yang F, Zhang S, Peng Q, Liu G, Zhao L, Choi HY, Xu Z, Zhou XJ. Ubiquitous coexisting electron-mode couplings in high-temperature cuprate superconductors. Proc Natl Acad Sci U S A 2023; 120:e2219491120. [PMID: 37851678 PMCID: PMC10614907 DOI: 10.1073/pnas.2219491120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 09/12/2023] [Indexed: 10/20/2023] Open
Abstract
In conventional superconductors, electron-phonon coupling plays a dominant role in generating superconductivity. In high-temperature cuprate superconductors, the existence of electron coupling with phonons and other boson modes and its role in producing high-temperature superconductivity remain unclear. The evidence of electron-boson coupling mainly comes from angle-resolved photoemission (ARPES) observations of [Formula: see text]70-meV nodal dispersion kink and [Formula: see text]40-meV antinodal kink. However, the reported results are sporadic and the nature of the involved bosons is still under debate. Here we report findings of ubiquitous two coexisting electron-mode couplings in cuprate superconductors. By taking ultrahigh-resolution laser-based ARPES measurements, we found that the electrons are coupled simultaneously with two sharp modes at [Formula: see text]70meV and [Formula: see text]40meV in different superconductors with different dopings, over the entire momentum space and at different temperatures above and below the superconducting transition temperature. These observations favor phonons as the origin of the modes coupled with electrons and the observed electron-mode couplings are unusual because the associated energy scales do not exhibit an obvious energy shift across the superconducting transition. We further find that the well-known "peak-dip-hump" structure, which has long been considered a hallmark of superconductivity, is also omnipresent and consists of "peak-double dip-double hump" finer structures that originate from electron coupling with two sharp modes. These results provide a unified picture for the [Formula: see text]70-meV and [Formula: see text]40-meV energy scales and their evolutions with momentum, doping and temperature. They provide key information to understand the origin of these energy scales and their role in generating anomalous normal state and high-temperature superconductivity.
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Affiliation(s)
- Hongtao Yan
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Jin Mo Bok
- Department of Physics, Pohang University of Science and Technology, Pohang37673, Korea
| | - Junfeng He
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Wentao Zhang
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Qiang Gao
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Xiangyu Luo
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Yongqing Cai
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Yingying Peng
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Jianqiao Meng
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Cong Li
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Hao Chen
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Chunyao Song
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Chaohui Yin
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Taimin Miao
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Yiwen Chen
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Genda Gu
- Condensed Matter Physics, Materials Science Division of Brookhaven National Laboratory, Upton, NY11973-5000
| | - Chengtian Lin
- Max Planck Institute for Solid State Research, D-70569Stuttgart, Germany
| | - Fengfeng Zhang
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing100190, China
| | - Feng Yang
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing100190, China
| | - Shenjin Zhang
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing100190, China
| | - Qinjun Peng
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing100190, China
| | - Guodong Liu
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
- Songshan Lake Materials Laboratory, Dongguan523808, China
| | - Lin Zhao
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
- Songshan Lake Materials Laboratory, Dongguan523808, China
| | - Han-Yong Choi
- Department of Physics, Sungkyunkwan University, Suwon16419, Korea
| | - Zuyan Xu
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing100190, China
| | - X. J. Zhou
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
- Songshan Lake Materials Laboratory, Dongguan523808, China
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
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3
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Valla T, Drozdov IK, Gu GD. Disappearance of superconductivity due to vanishing coupling in the overdoped Bi[Formula: see text]Sr[Formula: see text]CaCu[Formula: see text]O[Formula: see text]. Nat Commun 2020; 11:569. [PMID: 31996671 PMCID: PMC6989516 DOI: 10.1038/s41467-020-14282-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 12/24/2019] [Indexed: 11/09/2022] Open
Abstract
In cuprate superconductors, superconductivity is accompanied by a plethora of orders and phenomena that complicate our understanding of superconductivity in these materials. Prominent in the underdoped regime, these orders weaken or vanish with overdoping. Here, we approach the superconducting phase from the more conventional overdoped side. We present angle-resolved photoemission spectroscopy studies of Bi[Formula: see text]Sr[Formula: see text]CaCu[Formula: see text]O[Formula: see text], cleaved and annealed in ozone to increase the doping all the way to the non-superconducting phase. We show that the mass renormalization in the antinodal region of the Fermi surface that possibly reflects the pairing, weakens with doping and completely disappears precisely where superconductivity disappears. This is the evidence that in the overdoped regime, superconductivity is determined primarily by the coupling strength. A doping dependence and an abrupt disappearance above the transition temperature eliminate phononic mechanism of the observed renormalization and identify the onset of spin-fluctuations as its likely origin.
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Affiliation(s)
- T. Valla
- Condensed Matter Physics and Materials Science Department, Brookhaven National Lab, Upton, NY 11973 USA
| | - I. K. Drozdov
- Condensed Matter Physics and Materials Science Department, Brookhaven National Lab, Upton, NY 11973 USA
| | - G. D. Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Lab, Upton, NY 11973 USA
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4
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Bi-2212/1T-TaS 2 Van der Waals junctions: Interplay of proximity induced high-T c superconductivity and CDW order. Sci Rep 2017; 7:4639. [PMID: 28680063 PMCID: PMC5498642 DOI: 10.1038/s41598-017-04645-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 05/17/2017] [Indexed: 11/12/2022] Open
Abstract
Understanding the coexistence, competition and/or cooperation between superconductivity and charge density waves (CDWs) in the transition metal dichalcogenides (TMDs) is an elusive goal which, when realized, promises to reveal fundamental information on this important class of materials. Here, we use four-terminal current-voltage measurements to study the Van der Waals interface between freshly exfoliated flakes of the high-Tc superconductor, Bi-2212, and the CDW-dominated TMD layered material, 1T-TaS2. For highly transparent barriers, there is a pronounced Andreev reflection feature providing evidence for proximity-induced high-Tc superconductivity in 1T-TaS2 with a surprisingly large energy gap (~20 meV) equal to half that of intrinsic Bi-2212 (~40 meV). Our systematic study using conductance spectroscopy of junctions with different transparencies also reveals the presence of two separate boson modes, each associated with a “dip-hump” structure. We infer that the proximity-induced high-Tc superconductivity in the 1T-TaS2 is driven by coupling to the metastable metallic phase coexisting within the Mott commensurate CDW (CCDW) phase and associated with a concomitant change of the CCDW order parameter in the interfacial region.
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5
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Hlobil P, Jandke J, Wulfhekel W, Schmalian J. Tracing the Electronic Pairing Glue in Unconventional Superconductors via Inelastic Scanning Tunneling Spectroscopy. PHYSICAL REVIEW LETTERS 2017; 118:167001. [PMID: 28474901 DOI: 10.1103/physrevlett.118.167001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Indexed: 06/07/2023]
Abstract
Scanning tunneling microscopy has been shown to be a powerful experimental probe to detect electronic excitations and further allows us to deduce fingerprints of bosonic collective modes in superconductors. Here, we demonstrate that the inclusion of inelastic tunnel events is crucial for the interpretation of tunneling spectra of unconventional superconductors and allows us to directly probe electronic and bosonic excitations via scanning tunneling microscopy. We apply the formalism to the iron based superconductor LiFeAs. With the inclusion of inelastic contributions, we find strong evidence for a nonconventional pairing mechanism, likely via magnetic excitations.
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Affiliation(s)
- Patrik Hlobil
- Institut für Festkörperphysik, Karlsruher Institut für Technologie, 76344 Karlsruhe, Germany
- Institut für Theorie der Kondensierten Materie, Karlsruher Institut für Technologie, 76131 Karlsruhe, Germany
| | - Jasmin Jandke
- Physikalisches Institut, Karlsruher Institut für Technologie, 76131 Karlsruhe, Germany
| | - Wulf Wulfhekel
- Physikalisches Institut, Karlsruher Institut für Technologie, 76131 Karlsruhe, Germany
| | - Jörg Schmalian
- Institut für Festkörperphysik, Karlsruher Institut für Technologie, 76344 Karlsruhe, Germany
- Institut für Theorie der Kondensierten Materie, Karlsruher Institut für Technologie, 76131 Karlsruhe, Germany
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6
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Kloss T, Montiel X, de Carvalho VS, Freire H, Pépin C. Charge orders, magnetism and pairings in the cuprate superconductors. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:084507. [PMID: 27427401 DOI: 10.1088/0034-4885/79/8/084507] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We review the recent developments in the field of cuprate superconductors with special focus on the recently observed charge order in the underdoped compounds. We introduce new theoretical developments following the study of the antiferromagnetic quantum critical point in two dimensions, in which preemptive orders in both charge and superconducting (SC) sectors emerge, that are in turn related by an SU(2) symmetry. We consider the implications of this proliferation of orders in the underdoped region, and provide a study of the type of fluctuations which characterize the SU(2) symmetry. We identify an intermediate energy scale where the SC fluctuations are dominant and argue that they are unstable towards the formation of a resonant excitonic state at the pseudogap temperature T (*). We discuss the implications of this scenario for a few key experiments.
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Affiliation(s)
- T Kloss
- IPhT, L'Orme des Merisiers, CEA-Saclay, 91191 Gif-sur-Yvette, France
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7
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Gallais Y, Paul I, Chauvière L, Schmalian J. Nematic Resonance in the Raman Response of Iron-Based Superconductors. PHYSICAL REVIEW LETTERS 2016; 116:017001. [PMID: 26799039 DOI: 10.1103/physrevlett.116.017001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Indexed: 06/05/2023]
Abstract
In a fully gapped superconductor the electronic Raman response has a pair-breaking peak at twice the superconducting gap Δ, if the Bogoliubov excitations are uncorrelated. Motivated by the iron based superconductors, we study how this peak is modified if the superconducting phase hosts a nematic-structural quantum critical point. We show that, upon approaching this point by tuning, e.g., doping, the growth of nematic correlations between the quasiparticles transforms the pair-breaking peak into a nematic resonance. The mode energy is below 2Δ, and stays finite at the quantum critical point, where its spectral weight is sharply enhanced. The latter is consistent with recent experiments on electron-doped iron based superconductors and provides direct evidence of nematic correlations in their superconducting phases.
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Affiliation(s)
- Yann Gallais
- Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS, Université Paris Diderot, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - Indranil Paul
- Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS, Université Paris Diderot, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - Ludivine Chauvière
- Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS, Université Paris Diderot, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - Jörg Schmalian
- Institute for Theory of Condensed Matter, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
- Institute for Solid State Physics, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
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8
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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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9
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Greger M, Kollar M, Vollhardt D. Emergence of a common energy scale close to the orbital-selective Mott transition. PHYSICAL REVIEW LETTERS 2013; 110:046403. [PMID: 25166180 DOI: 10.1103/physrevlett.110.046403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Indexed: 06/03/2023]
Abstract
We calculate the spectra and spin susceptibilities of a Hubbard model with two bands having different bandwidths but the same on-site interaction, with parameters close to the orbital-selective Mott transition, using dynamical mean-field theory. If the Hund's rule coupling is sufficiently strong, one common energy scale emerges which characterizes both the location of kinks in the self-energy and extrema of the diagonal spin susceptibilities. A physical explanation of this energy scale is derived from a Kondo-type model. We infer that for multiband systems local spin dynamics rather than spectral functions determine the location of kinks in the effective band structure.
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Affiliation(s)
- Markus Greger
- Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - Marcus Kollar
- Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - Dieter Vollhardt
- Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
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10
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Chi S, Grothe S, Liang R, Dosanjh P, Hardy WN, Burke SA, Bonn DA, Pennec Y. Scanning tunneling spectroscopy of superconducting LiFeAs single crystals: evidence for two nodeless energy gaps and coupling to a bosonic mode. PHYSICAL REVIEW LETTERS 2012; 109:087002. [PMID: 23002767 DOI: 10.1103/physrevlett.109.087002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Indexed: 06/01/2023]
Abstract
The superconducting compound LiFeAs is studied by scanning tunneling microscopy and spectroscopy. A gap map of the unreconstructed surface indicates a high degree of homogeneity in this system. Spectra at 2 K show two nodeless superconducting gaps with Δ(1)=5.3±0.1 meV and Δ(2)=2.5±0.2 meV. The gaps close as the temperature is increased to the bulk T(c), indicating that the surface accurately represents the bulk. A dip-hump structure is observed below T(c) with an energy scale consistent with a magnetic resonance recently reported by inelastic neutron scattering.
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Affiliation(s)
- Shun Chi
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada
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11
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Johnston S, Vishik IM, Lee WS, Schmitt F, Uchida S, Fujita K, Ishida S, Nagaosa N, Shen ZX, Devereaux TP. Evidence for the importance of extended Coulomb interactions and forward scattering in cuprate superconductors. PHYSICAL REVIEW LETTERS 2012; 108:166404. [PMID: 22680740 DOI: 10.1103/physrevlett.108.166404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 12/13/2011] [Indexed: 06/01/2023]
Abstract
The prevalent view of the high-temperature superconducting cuprates is that their essential low-energy physics is captured by local Coulomb interactions. However, this view been challenged recently by studies indicating the importance of longer-range components. Motivated by this, we demonstrate the importance of these components by examining the electron-phonon (e-ph) interaction with acoustic phonons in connection with the recently discovered renormalization in the near-nodal low-energy (~8-15 meV) dispersion of Bi(2)Sr(2)CaCu(2)O(8+δ). By studying its nontrivial momentum and doping dependence we conclude a predominance of forward scattering arising from the direct interplay between the e-ph and extended Coulomb interactions. Our results thus demonstrate how the low-energy renormalization can provide a pathway to new insights into how these interactions interplay with one another and influence pairing and dynamics in the cuprates.
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Affiliation(s)
- S Johnston
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, Menlo Park, California 94305, USA
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12
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First direct observation of the Van Hove singularity in the tunnelling spectra of cuprates. Nat Commun 2011; 2:221. [PMID: 21364560 PMCID: PMC3072078 DOI: 10.1038/ncomms1229] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 02/03/2011] [Indexed: 11/08/2022] Open
Abstract
In two-dimensional (2D) lattices, the electronic levels are unevenly spaced, and the density of states (DOS) displays a logarithmic divergence known as the Van Hove singularity (VHS). This is the case in particular for the layered cuprate superconductors. The scanning tunnelling microscope (STM) probes the DOS, and is therefore the ideal tool to observe the VHS. No STM study of cuprate superconductors has reported such an observation so far giving rise to a debate about the possibility of observing directly the normal state DOS in the tunnelling spectra. In this study, we show for the first time that the VHS is unambiguously observed in STM measurements performed on the cuprate Bi₂Sr₂CuO(₆+δ) (Bi-2201). Beside closing the debate, our analysis proves the presence of the pseudogap in the overdoped side of the phase diagram of Bi-2201 and discredits the scenario of the pseudogap phase crossing the superconducting dome.
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Sebastian SE, Harrison N, Lonzarich GG. Quantum oscillations in the high-Tc cuprates. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2011; 369:1687-1711. [PMID: 21422021 DOI: 10.1098/rsta.2010.0243] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We review recent progress in the study of quantum oscillations as a tool for uniquely probing low-energy electronic excitations in high-T(c) cuprate superconductors. Quantum oscillations in the underdoped cuprates reveal that a close correspondence with Landau Fermi-liquid behaviour persists in the accessed regions of the phase diagram, where small pockets are observed. Quantum oscillation results are viewed in the context of momentum-resolved probes such as photoemission, and evidence examined from complementary experiments for potential explanations for the transformation from a large Fermi surface into small sections. Indications from quantum oscillation measurements of a low-energy Fermi surface instability at low dopings under the superconducting dome at the metal-insulator transition are reviewed, and potential implications for enhanced superconducting temperatures are discussed.
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Affiliation(s)
- Suchitra E Sebastian
- Department of Physics, Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, UK.
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14
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Ahmadi O, Coffey L, Zasadzinski JF, Miyakawa N, Ozyuzer L. Eliashberg analysis of tunneling experiments: support for the pairing glue hypothesis in cuprate superconductors. PHYSICAL REVIEW LETTERS 2011; 106:167005. [PMID: 21599405 DOI: 10.1103/physrevlett.106.167005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Indexed: 05/30/2023]
Abstract
Evidence for the validity of the pairing glue interpretation of high temperature superconductivity is presented using a modified Eliashberg analysis of experimental superconductor-insulator-superconductor (SIS) tunneling data in B2Sr2CaCu2O8 (Bi2212) over a wide range of doping. This is accomplished by extracting detailed information on the diagonal and anomalous contributions to the quasiparticle self-energy. In particular, a comparison of the imaginary part of the anomalous self-energy ImΦ(ω) and the pairing glue spectral function α2F(ω) used in the model is consistent with Hubbard model simulations in the literature. In addition, the real part of the diagonal self-energy for optimal doped Bi2212 bears a strong resemblance to that obtained from photoemission experiments.
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Affiliation(s)
- O Ahmadi
- Physics Department, Illinois Institute of Technology, Chicago, Illinois 60616, USA
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15
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Fasano Y, Maggio-Aprile I, Zhigadlo ND, Katrych S, Karpinski J, Fischer Ø. Local quasiparticle density of states of superconducting SmFeAsO(1-x)F(x) single crystals: evidence for spin-mediated pairing. PHYSICAL REVIEW LETTERS 2010; 105:167005. [PMID: 21231000 DOI: 10.1103/physrevlett.105.167005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Indexed: 05/30/2023]
Abstract
We probe the local quasiparticles density of states in micron-sized SmFeAsO(1-x)F(x) single crystals by means of scanning tunnelling spectroscopy. Spectral features resemble those of cuprates, particularly a dip-hump-like structure developed at energies larger than the gap that can be ascribed to the coupling of quasiparticles to a collective mode, quite likely a resonant spin mode. The energy of the collective mode revealed in our study decreases when the pairing strength increases. Our findings support spin-fluctuation-mediated pairing in pnictides.
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Affiliation(s)
- Y Fasano
- DPMC-MaNEP, University of Geneva, Geneva, Switzerland
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16
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Jenkins N, Fasano Y, Berthod C, Maggio-Aprile I, Piriou A, Giannini E, Hoogenboom BW, Hess C, Cren T, Fischer Ø. Imaging the essential role of spin fluctuations in high-T(c) superconductivity. PHYSICAL REVIEW LETTERS 2009; 103:227001. [PMID: 20366120 DOI: 10.1103/physrevlett.103.227001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 09/14/2009] [Indexed: 05/29/2023]
Abstract
We have used scanning tunneling spectroscopy to investigate short-length electronic correlations in three-layer Bi2Sr2Ca2Cu3O(10+delta) (Bi-2223). We show that the superconducting gap and the energy Omega(dip), defined as the difference between the dip minimum and the gap, are both modulated in space following the lattice superstructure and are locally anticorrelated. Based on fits of our data to a microscopic strong-coupling model, we show that Omega(dip) is an accurate measure of the collective-mode energy in Bi-2223. We conclude that the collective mode responsible for the dip is a local excitation with a doping dependent energy and is most likely the (pi, pi) spin resonance.
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Affiliation(s)
- N Jenkins
- DPMC-MaNEP, University of Geneva, 24 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
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17
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Shen ZX, Lanzara A, Ishihara S, Nagaosa N. Role of the electron-phonon interaction in the strongly correlated cuprate superconductors. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/13642810208220725] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Z.-X. Shen
- a Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory , Stanford University , California , 94305 , USA
| | - A. Lanzara
- a Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory , Stanford University , California , 94305 , USA
- b Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley , California , 94720 , USA
| | - S. Ishihara
- c Department of Applied Physics , University of Tokyo , Bunkyo-ku, Tokyo , 113-8656 , Japan
| | - N. Nagaosa
- c Department of Applied Physics , University of Tokyo , Bunkyo-ku, Tokyo , 113-8656 , Japan
- d Correlated Electron Research Center, Agency of Industrial Science and Technology , Tsukuba , 305-0046 , Japan
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18
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Mishchenko AS. Electron - phonon coupling in underdoped high-temperature superconductors. ACTA ACUST UNITED AC 2009. [DOI: 10.3367/ufnr.0179.200912b.1259] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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19
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de Castro GL, Berthod C, Piriou A, Giannini E, Fischer Ø. Preeminent role of the van Hove singularity in the strong-coupling analysis of scanning tunneling spectroscopy for two-dimensional cuprate superconductors. PHYSICAL REVIEW LETTERS 2008; 101:267004. [PMID: 19437664 DOI: 10.1103/physrevlett.101.267004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In two dimensions the noninteracting density of states displays a van Hove singularity (VHS) which introduces an intrinsic electron-hole asymmetry, absent in three dimensions. We show that due to this VHS the strong-coupling analysis of tunneling spectra in high-Tc superconductors must be reconsidered. Based on a microscopic model which reproduces the experimental data with excellent accuracy, we elucidate the peculiar role played by the VHS in shaping the tunneling spectra, and show that more conventional analysis of strong-coupling effects can lead to severe errors.
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20
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Chubukov AV, Gor'kov LP. Spin resonance in three-dimensional superconductors: the case of CeCoIn5. PHYSICAL REVIEW LETTERS 2008; 101:147004. [PMID: 18851562 DOI: 10.1103/physrevlett.101.147004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Indexed: 05/26/2023]
Abstract
The recent observation of resonance spin excitation at (1/2, 1/2, 1/2) in the superconducting state of CeCoIn5 [C. Stock, Phys. Rev. Lett. 100, 087001 (2008)10.1103/Phys. Rev. Lett.100.087001] was interpreted as evidence for d{x{2}-y{2}} gap symmetry, by analogy with cuprates. This is true if the resonance is a spin exciton. We argue that such a description is undermined by the three dimensionality of CeCoIn5. We show that in 3D systems the excitonic resonance only emerges at strong coupling, and is weak. We argue in favor of the alternative, magnon scenario, which does not require a d{x{2}-y{2}} gap.
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Affiliation(s)
- A V Chubukov
- Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA
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21
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Wei J, Zhang Y, Ou HW, Xie BP, Shen DW, Zhao JF, Yang LX, Arita M, Shimada K, Namatame H, Taniguchi M, Yoshida Y, Eisaki H, Feng DL. Superconducting coherence peak in the electronic excitations of a single-layer Bi2Sr1.6La0.4CuO6+delta cuprate superconductor. PHYSICAL REVIEW LETTERS 2008; 101:097005. [PMID: 18851643 DOI: 10.1103/physrevlett.101.097005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Indexed: 05/26/2023]
Abstract
Angle resolved photoemission spectroscopy study is reported on a high quality optimally doped Bi2Sr1.6La0.4CuO6+delta high-Tc superconductor. In the antinodal region with a maximal d-wave gap, the symbolic superconducting coherence peak, which has been widely observed in multi-CuO2-layer cuprate superconductors, is unambiguously observed in a single-layer system. The associated peak-dip separation is just about 19 meV, which is much smaller than its counterparts in multilayered compounds, but correlates with the energy scales of spin excitations in single-layer cuprates.
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Affiliation(s)
- J Wei
- Department of Physics, Surface Physics Laboratory (National Key Laboratory), Fudan University, Shanghai 200433, People's Republic of China
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22
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Small phonon contribution to the photoemission kink in the copper oxide superconductors. Nature 2008; 452:975-8. [DOI: 10.1038/nature06874] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Accepted: 02/21/2008] [Indexed: 11/09/2022]
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23
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Zhang W, Liu G, Zhao L, Liu H, Meng J, Dong X, Lu W, Wen JS, Xu ZJ, Gu GD, Sasagawa T, Wang G, Zhu Y, Zhang H, Zhou Y, Wang X, Zhao Z, Chen C, Xu Z, Zhou XJ. Identification of a new form of electron coupling in the Bi2Sr2CaCu2O8 superconductor by laser-based angle-resolved photoemission spectroscopy. PHYSICAL REVIEW LETTERS 2008; 100:107002. [PMID: 18352224 DOI: 10.1103/physrevlett.100.107002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Indexed: 05/26/2023]
Abstract
Laser-based angle-resolved photoemission measurements with superhigh resolution have been carried out on an optimally doped Bi(2)Sr(2)CaCu(2)O(8) high temperature superconductor. New high energy features at approximately 115 meV and approximately 150 meV, in addition to the prominent approximately 70 meV one, are found to develop in the nodal electron self-energy in the superconducting state. These high energy features, which cannot be attributed to electron coupling with single phonon or magnetic resonance mode, point to the existence of a new form of electron coupling in high temperature superconductors.
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Affiliation(s)
- Wentao Zhang
- National Laboratory for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China
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24
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Zhu JX, McElroy K, Lee J, Devereaux TP, Si Q, Davis JC, Balatsky AV. Effects of pairing potential scattering on Fourier-transformed inelastic tunneling spectra of high-Tc cuprate superconductors with bosonic modes. PHYSICAL REVIEW LETTERS 2006; 97:177001. [PMID: 17155496 DOI: 10.1103/physrevlett.97.177001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 08/09/2006] [Indexed: 05/12/2023]
Abstract
Recent scanning tunneling microscopy (STM) experimentally observed strong gap inhomogeneity in Bi2Sr2CaCu2O(8+delta) (BSCCO). We argue that disorder in the pair potential underlies the gap inhomogeneity, and investigate its role in the Fourier-transformed inelastic tunneling spectra as revealed in the STM. We find that the random pair potential induces unique q-space patterns in the local density of states (LDOS) of a d-wave superconductor. We consider the effects of electron coupling to various bosonic modes and find the pattern of LDOS modulation due to coupling to the B(1g) phonon mode to be consistent with the one observed in the inelastic electron tunnneling STM experiment in BSCCO. These results suggest strong electron-lattice coupling as an essential part of the superconducting state in high-Tc materials.
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Affiliation(s)
- Jian-Xin Zhu
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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25
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Kordyuk AA, Borisenko SV, Zabolotnyy VB, Geck J, Knupfer M, Fink J, Büchner B, Lin CT, Keimer B, Berger H, Pan AV, Komiya S, Ando Y. Constituents of the quasiparticle spectrum along the nodal direction of high-Tc cuprates. PHYSICAL REVIEW LETTERS 2006; 97:017002. [PMID: 16907398 DOI: 10.1103/physrevlett.97.017002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Indexed: 05/11/2023]
Abstract
Applying the Kramers-Kronig consistent procedure, developed earlier, we investigate in detail the formation of the quasiparticle spectrum along the nodal direction of high-Tc cuprates. The heavily discussed "70 meV kink" on the renormalized dispersion exhibits a strong temperature and doping dependence when purified from structural effects such as bilayer splitting, diffraction replicas, etc. This dependence is well understood in terms of fermionic and bosonic constituents of the self-energy. The latter follows the evolution of the spin-fluctuation spectrum, emerging below some doping dependent temperature and sharpening below Tc, and is mainly responsible for the formation of the kink in question.
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Affiliation(s)
- A A Kordyuk
- Institut für Festkoerper und Werkstofforschung Dresden, Post Office Box 270116, D-01171 Dresden, Germany
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26
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Borisenko SV, Kordyuk AA, Koitzsch A, Fink J, Geck J, Zabolotnyy V, Knupfer M, Büchner B, Berger H, Falub M, Shi M, Krempasky J, Patthey L. Parity of the pairing bosons in a high-temperature Pb-Bi2Sr2CaCu2O8 bilayer superconductor by angle-resolved photoemission spectroscopy. PHYSICAL REVIEW LETTERS 2006; 96:067001. [PMID: 16606032 DOI: 10.1103/physrevlett.96.067001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2005] [Indexed: 05/08/2023]
Abstract
We report the observation of a novel effect in the bilayer Pb-Bi2Sr2CaCu2O8 (Pb-Bi2212) high-T(c) superconductor by means of angle-resolved photoemission with circularly polarized excitation. Different scattering rates, determined as a function of energy separately for the bonding and antibonding copper-oxygen bands, strongly imply that the dominating scattering channel is odd with respect to layer exchange within a bilayer. This is inconsistent with a phonon-mediated scattering and favors the participation of the odd collective spin excitations in the scattering mechanism in near-nodal regions of the k space, suggesting a magnetic nature of the pairing mediator.
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Affiliation(s)
- S V Borisenko
- Leibniz-Institute for Solid State Research, IFW-Dresden, P.O. Box 270116, D-01171 Dresden, Germany
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27
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Devereaux TP, Cuk T, Shen ZX, Nagaosa N. Anisotropic electron-phonon interaction in the cuprates. PHYSICAL REVIEW LETTERS 2004; 93:117004. [PMID: 15447371 DOI: 10.1103/physrevlett.93.117004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2004] [Indexed: 05/15/2023]
Abstract
We explore manifestations of electron-phonon coupling on the electron spectral function for two phonon modes in the cuprates exhibiting strong renormalizations with temperature and doping. Applying simple symmetry considerations and kinematic constraints, we find that the out-of-plane, out-of-phase O buckling mode (B(1g)) involves small momentum transfers and couples strongly to electronic states near the antinode while the in-plane Cu-O breathing modes involve large momentum transfers and couples strongly to nodal electronic states. Band renormalization effects are found to be strongest in the superconducting state near the antinode, in full agreement with angle-resolved photoemission spectroscopy data.
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Affiliation(s)
- T P Devereaux
- Department of Physics, University of Waterloo, Ontario, Canada N2L 3GI
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28
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Schäfer J, Schrupp D, Rotenberg E, Rossnagel K, Koh H, Blaha P, Claessen R. Electronic quasiparticle renormalization on the spin wave energy scale. PHYSICAL REVIEW LETTERS 2004; 92:097205. [PMID: 15089509 DOI: 10.1103/physrevlett.92.097205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2003] [Indexed: 05/24/2023]
Abstract
High-resolution photoemission data of the (110) iron surface reveal the existence of well-defined metallic surface resonances in good correspondence to band calculations. Close to the Fermi level, their dispersion and momentum broadening display anomalies characteristic of quasiparticle renormalization due to coupling to bosonic excitations. Its energy scale exceeds that of phonons by far, and is in striking coincidence with that of the spin wave spectrum in iron. The self-energy behavior thus gives spectroscopic evidence of a quasiparticle mass enhancement due to electron-magnon coupling.
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Affiliation(s)
- J Schäfer
- Institut für Physik, Universität Augsburg, 86135 Augsburg, Germany
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29
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Zhu JX, Sun J, Si Q, Balatsky AV. Effects of a collective spin resonance mode on the scanning tunneling microscopy spectra of d-wave superconductors. PHYSICAL REVIEW LETTERS 2004; 92:017002. [PMID: 14754011 DOI: 10.1103/physrevlett.92.017002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2003] [Indexed: 05/24/2023]
Abstract
A high-energy spin resonance mode is known to exist in many high-temperature superconductors. Motivated by recent scanning tunneling microscopy experiments in superconducting Bi(2)Sr(2)CaCu(2)O(8+delta), we study the effects of this resonance mode on the local density of states (LDOS). The coupling between the electrons in a d-wave superconductor and the resonance mode produces high-energy peaks in the LDOS, which displays a two-unit-cell periodic modulation around a nonmagnetic impurity. This suggests a new means to not only detect the dynamical spin collective mode but also study its coupling to electronic excitations.
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Affiliation(s)
- Jian-Xin Zhu
- Theoretical Division, MS B262, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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30
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Kim TK, Kordyuk AA, Borisenko SV, Koitzsch A, Knupfer M, Berger H, Fink J. Doping dependence of the mass enhancement in (Pb,Bi)2Sr2CaCu2O8 at the antinodal point in the superconducting and normal states. PHYSICAL REVIEW LETTERS 2003; 91:167002. [PMID: 14611429 DOI: 10.1103/physrevlett.91.167002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2003] [Indexed: 05/24/2023]
Abstract
Angle-resolved photoemission spectroscopy is used to study the mass renormalization of the charge carriers in the high-T(c) superconductor (Pb,Bi)2Sr2CaCu2O8 in the vicinity of the (pi,0) point in the superconducting and the normal states. Using matrix element effects at different photon energies and due to a high momentum and energy resolution the bonding and the antibonding bands could be separated in the whole dopant range. A huge coupling to a bosonic collective mode is observed below T(c) for both bands, in particular, for the underdoped case. Above T(c), a weaker coupling to a continuous spectrum of modes is detected.
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Affiliation(s)
- T K Kim
- Leibniz-Institute for Solid State and Materials Research Dresden, P.O.Box 270116, D-01171 Dresden, Germany
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31
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Borisenko SV, Kordyuk AA, Kim TK, Koitzsch A, Knupfer M, Fink J, Golden MS, Eschrig M, Berger H, Follath R. Anomalous enhancement of the coupling to the magnetic resonance mode in underdoped Pb-Bi2212. PHYSICAL REVIEW LETTERS 2003; 90:207001. [PMID: 12785915 DOI: 10.1103/physrevlett.90.207001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2002] [Indexed: 05/24/2023]
Abstract
High-resolution angle-resolved photoemission with variable excitation energies is used to disentangle bilayer splitting effects and intrinsic (self-energy) effects in the electronic spectral function near the (pi,0) point of differently doped (Pb,Bi)(2)Sr(2)CaCu(2)O(8+delta). In contrast to overdoped samples, where intrinsic effects at the (pi,0) point are virtually absent, we find in underdoped samples intrinsic effects in the superconducting-state (pi,0) spectra of the antibonding band. This intrinsic effect is present only below the critical temperature and weakens considerably with doping. Our results give strong support for models which involve a strong coupling of electronic excitations with the resonance mode seen in inelastic neutron scattering experiments.
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Affiliation(s)
- S V Borisenko
- Institute for Solid State Research, IFW-Dresden, P.O. Box 270116, D-01171 Dresden, Germany
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32
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Yurgens A, Winkler D, Claeson T, Ono S, Ando Y. Intrinsic tunneling spectra of Bi2(Sr(2-x)Lax)CuO(6+delta). PHYSICAL REVIEW LETTERS 2003; 90:147005. [PMID: 12731942 DOI: 10.1103/physrevlett.90.147005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2002] [Indexed: 05/24/2023]
Abstract
We have measured intrinsic-tunneling spectra of a single CuO-layer La-doped Bi2(Sr(2-x)Lax)CuO(6+delta) (Bi2201-Lax). Despite a difference of a factor of 3 in the optimal superconducting critical temperatures for Bi2201-La0.4 and Bi2212 (32 and 95 K, respectively) and different spectral energy scales, we find that the pseudogap vanishes at a similar characteristic temperature T* approximately 230-300 K for both compounds. We find also that, in Bi2201-Lax, pseudogap humps are seen as sharp peaks and, in fact, even dominate the intrinsic spectra.
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Affiliation(s)
- A Yurgens
- Chalmers University of Technology, S-41296 Göteborg, Sweden
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33
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Eschrig M, Norman MR. Dispersion anomalies in bilayer cuprates and the odd symmetry of the magnetic resonance. PHYSICAL REVIEW LETTERS 2002; 89:277005. [PMID: 12513236 DOI: 10.1103/physrevlett.89.277005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2002] [Indexed: 05/24/2023]
Abstract
We demonstrate that recent angle resolved photoemission data in bilayer cuprate superconductors imply that scattering of electrons between bonding and antibonding bands is strong compared to scattering within these bands. As a consequence, the resulting data can be reproduced only by a model which assumes that the electrons are interacting with a bosonic mode that is odd with respect to the layer indices. This odd symmetry is a unique property of the magnetic resonance observed by inelastic neutron scattering.
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Affiliation(s)
- M Eschrig
- Institut für Theoretische Festkörperphysik, Universität Karlsruhe, 76128 Karlsruhe, Germany
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34
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Abanov A, Chubukov AV, Eschrig M, Norman MR, Schmalian J. Neutron resonance in the cuprates and its effect on fermionic excitations. PHYSICAL REVIEW LETTERS 2002; 89:177002. [PMID: 12398698 DOI: 10.1103/physrevlett.89.177002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2001] [Indexed: 05/24/2023]
Abstract
We argue that the exciton scenario for the magnetic resonance in the cuprate superconductors yields a small spectral weight of the resonance, in agreement with experiment. We show that the small weight is related to its concentration in a small region of momentum and energy. Despite this, we find that a large fermionic self-energy can indeed be generated by a resonance with such properties, i.e., the scattering from the resonance substantially affects the electronic properties of the cuprates below T(c).
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Affiliation(s)
- Ar Abanov
- Theory Division, Los Alamos National Laboratory, MS B262, Los Alamos, New Mexico 87545, USA
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35
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Bogdanov PV, Lanzara A, Zhou XJ, Yang WL, Eisaki H, Hussain Z, Shen ZX. Anomalous momentum dependence of the quasiparticle scattering rate in overdoped Bi2Sr2CaCu2O8. PHYSICAL REVIEW LETTERS 2002; 89:167002. [PMID: 12398747 DOI: 10.1103/physrevlett.89.167002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2002] [Indexed: 05/24/2023]
Abstract
The question of the anisotropy of the electron scattering in high temperature superconductors is investigated using high resolution angle-resolved photoemission data from Pb-doped Bi2Sr2CaCu2O8 (Bi2212) with suppressed superstructure. The scattering rate of low energy electrons along two bilayer-split pieces of the Fermi surface is measured (via the quasiparticle peak width), and no increase of scattering towards the antinode (pi,0) region is observed, contradicting the expectation from Q=(pi,pi) scattering. The results put a limit on the effects of Q=(pi,pi) scattering on the electronic structure of this overdoped superconductor with still very high T(c).
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Affiliation(s)
- P V Bogdanov
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, California 94305, USA
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36
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Kee HY, Kivelson SA, Aeppli G. Spin-1 neutron resonance peak cannot account for electronic anomalies in the cuprate superconductors. PHYSICAL REVIEW LETTERS 2002; 88:257002. [PMID: 12097119 DOI: 10.1103/physrevlett.88.257002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2001] [Indexed: 05/23/2023]
Abstract
In certain cuprates, a spin-1 resonance mode is prominent in the magnetic structure measured by neutron scattering. It has been proposed that this mode is responsible for significant features seen in other spectroscopies, such as photoemission and optical absorption, which are sensitive to the charge dynamics, and even that this mode is the boson responsible for "mediating" the superconducting pairing. We show that its small (measured) intensity and weak coupling to electron-hole pairs (as deduced from the measured lifetime) disqualifies the resonant mode from either proposed role.
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Affiliation(s)
- Hae-Young Kee
- Department of Physics, University of California-Los Angeles, Los Angeles, California 90095-1547, USA
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37
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He H, Bourges P, Sidis Y, Ulrich C, Regnault LP, Pailhès S, Berzigiarova NS, Kolesnikov NN, Keimer B. Magnetic resonant mode in the single-layer high-temperature superconductor Tl2Ba2CuO(6+delta). Science 2002; 295:1045-7. [PMID: 11809938 DOI: 10.1126/science.1067877] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
An unusual spin excitation mode observed by neutron scattering has inspired numerous theoretical studies of the interplay between charged quasiparticles and collective spin excitations in the copper oxide high-temperature superconductors. The mode has, thus far, only been observed in materials with crystal structures consisting of copper oxide bilayers, and it is absent in the single-layer compound La(2-x)Sr(x)CuO(4+delta). Neutron-scattering data now show that the mode is present in Tl(2)Ba(2)CuO(6+delta), a single-layer compound with a superconducting transition temperature of approximately 90 kelvin, demonstrating that it is a generic feature of the copper oxide superconductors, independent of the layer sequence. This restricts the theoretical models for the origin of the resonant mode and its role in the mechanism of high-temperature superconductivity.
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Affiliation(s)
- H He
- Max-Planck-Institut für Festkörperforschung, 70569 Stuttgart, Germany
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38
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Johnson PD, Valla T, Fedorov AV, Yusof Z, Wells BO, Li Q, Moodenbaugh AR, Gu GD, Koshizuka N, Kendziora C, Jian S, Hinks DG. Doping and temperature dependence of the mass enhancement observed in the cuprate Bi(2)Sr(2)CaCu(2)O(8+delta). PHYSICAL REVIEW LETTERS 2001; 87:177007. [PMID: 11690300 DOI: 10.1103/physrevlett.87.177007] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2001] [Indexed: 05/23/2023]
Abstract
High-resolution photoemission is used to study the electronic structure of the cuprate superconductor, Bi(2)Sr(2)CaCu(2)O(8+delta), as a function of hole doping and temperature. A kink observed in the band dispersion in the nodal line in the superconducting state is associated with coupling to a resonant mode observed in neutron scattering. From the measured real part of the self-energy it is possible to extract a coupling constant which is largest in the underdoped regime, then decreasing continuously into the overdoped regime.
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Affiliation(s)
- P D Johnson
- Department of Physics, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
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39
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Manske D, Eremin I, Bennemann KH. Analysis of the elementary excitations in high-T(c) cuprates: explanation of the new energy scale observed by angle-resolved photoemission spectroscopy. PHYSICAL REVIEW LETTERS 2001; 87:177005. [PMID: 11690298 DOI: 10.1103/physrevlett.87.177005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2001] [Indexed: 05/23/2023]
Abstract
We analyze the energy and momentum dependence of the elementary excitations in high- T(c) superconductors resulting from the coupling to spin fluctuations. As a result of the energy dependence of the self-energy Sigma(k,omega), characteristic features occur in the spectral density explaining the "kink" in recent angle-resolved photoemission spectroscopy experiments. We present results for the spectral density A(k,omega) for the feedback of superconductivity on the excitations, and for the superconducting order parameter Delta(k,omega). These results relate also to inelastic neutron scattering and tunneling experiments and shed important light on the essential ingredients a theory of the elementary excitations in the cuprates must contain.
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Affiliation(s)
- D Manske
- Institut für Theoretische Physik, Freie Universität Berlin, D-14195 Berlin, Germany
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40
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McQueeney RJ, Sarrao JL, Pagliuso PG, Stephens PW, Osborn R. Mixed lattice and electronic states in high-temperature superconductors. PHYSICAL REVIEW LETTERS 2001; 87:077001. [PMID: 11497908 DOI: 10.1103/physrevlett.87.077001] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2001] [Indexed: 05/23/2023]
Abstract
Inelastic neutron scattering measurements are presented which show the abrupt development of new oxygen lattice vibrations near the doping-induced metal-insulator transition in La(2--x)Sr(x)CuO(4). A direct correlation is established between these lattice modes and the electronic susceptibility (as measured by photoemission) inferring that such modes mix strongly with charge fluctuations. This electron-lattice coupling can be characterized as a localized one-dimensional response of the lattice to short-ranged metallic charge fluctuations.
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Affiliation(s)
- R J McQueeney
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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41
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Zasadzinski JF, Ozyuzer L, Miyakawa N, Gray KE, Hinks DG, Kendziora C. Correlation of tunneling spectra in Bi(2)Sr(2)CaCu(2)O(8+delta) with the resonance spin excitation. PHYSICAL REVIEW LETTERS 2001; 87:067005. [PMID: 11497847 DOI: 10.1103/physrevlett.87.067005] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2000] [Indexed: 05/23/2023]
Abstract
New break-junction tunneling data are reported in Bi(2)Sr(2)CaCu(2)O(8+delta) over a wide range of hole concentration from underdoped (T(c) = 74 K) to optimal doped (T(c) = 95 K) to overdoped (T(c) = 48 K). The conductances exhibit sharp dips at a voltage, Omega/e, measured with respect to the superconducting gap. Clear trends are found such that the dip strength is maximum at optimal doping and that Omega scales as 4.9kT(c) over the entire doping range. These features link the dip to the resonance spin excitation and suggest quasiparticle interactions with this mode are important for superconductivity.
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Affiliation(s)
- J F Zasadzinski
- Physics Division, Illinois Institute of Technology, Chicago, Illinois 60616, USA
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42
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Lanzara A, Bogdanov PV, Zhou XJ, Kellar SA, Feng DL, Lu ED, Yoshida T, Eisaki H, Fujimori A, Kishio K, Shimoyama JI, Noda T, Uchida S, Hussain Z, Shen ZX. Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors. Nature 2001; 412:510-4. [PMID: 11484045 DOI: 10.1038/35087518] [Citation(s) in RCA: 230] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Coupling between electrons and phonons (lattice vibrations) drives the formation of the electron pairs responsible for conventional superconductivity. The lack of direct evidence for electron-phonon coupling in the electron dynamics of the high-transition-temperature superconductors has driven an intensive search for an alternative mechanism. A coupling of an electron with a phonon would result in an abrupt change of its velocity and scattering rate near the phonon energy. Here we use angle-resolved photoemission spectroscopy to probe electron dynamics-velocity and scattering rate-for three different families of copper oxide superconductors. We see in all of these materials an abrupt change of electron velocity at 50-80 meV, which we cannot explain by any known process other than to invoke coupling with the phonons associated with the movement of the oxygen atoms. This suggests that electron-phonon coupling strongly influences the electron dynamics in the high-temperature superconductors, and must therefore be included in any microscopic theory of superconductivity.
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Affiliation(s)
- A Lanzara
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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43
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Krasnov VM, Kovalev AE, Yurgens A, Winkler D. Magnetic field dependence of the superconducting gap and the pseudogap in Bi2212 and HgBr2-Bi2212, studied by intrinsic tunneling spectroscopy. PHYSICAL REVIEW LETTERS 2001; 86:2657-2660. [PMID: 11290004 DOI: 10.1103/physrevlett.86.2657] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2000] [Indexed: 05/23/2023]
Abstract
Intrinsic tunneling spectroscopy in high magnetic field (H) is used for a direct test of superconducting features in the quasiparticle density of states of pure Bi2212 and intercalated HgBr2-Bi2212 high- T(c) superconductors. We were able to distinguish with great clarity two coexisting gaps: (i) the superconducting gap, which closes as H-->H(c2)(T), and (ii) the c-axis pseudogap, which does not change either with H or with T. Strikingly different H dependencies, together with previously observed different temperature dependencies of the two gaps, speak against a superconducting origin of the pseudogap.
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Affiliation(s)
- V M Krasnov
- Department of Microelectronics and Nanoscience, Chalmers University of Technology, Göteborg, Sweden
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44
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Kaminski A, Randeria M, Campuzano JC, Norman MR, Fretwell H, Mesot J, Sato T, Takahashi T, Kadowaki K. Renormalization of spectral line shape and dispersion below Tc in Bi2Sr2CaCu2O8+delta. PHYSICAL REVIEW LETTERS 2001; 86:1070-1073. [PMID: 11178012 DOI: 10.1103/physrevlett.86.1070] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2000] [Indexed: 05/23/2023]
Abstract
Angle-resolved photoemission data in the superconducting state of Bi2Sr2CaCu2O8+delta show a kink in the dispersion along the zone diagonal, which is related via a Kramers-Krönig analysis to a drop in the low energy scattering rate. As one moves towards (pi,0), this kink evolves into a spectral dip. The occurrence of these anomalies in the dispersion and line shape throughout the zone indicates the presence of a new energy scale in the superconducting state.
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Affiliation(s)
- A Kaminski
- Department of Physics, University of Illinois at Chicago, 60607, USA
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