1
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Parzyck CT, Gupta NK, Wu Y, Anil V, Bhatt L, Bouliane M, Gong R, Gregory BZ, Luo A, Sutarto R, He F, Chuang YD, Zhou T, Herranz G, Kourkoutis LF, Singer A, Schlom DG, Hawthorn DG, Shen KM. Absence of 3a 0 charge density wave order in the infinite-layer nickelate NdNiO 2. Nat Mater 2024; 23:486-491. [PMID: 38278983 PMCID: PMC10990928 DOI: 10.1038/s41563-024-01797-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/03/2024] [Indexed: 01/28/2024]
Abstract
A hallmark of many unconventional superconductors is the presence of many-body interactions that give rise to broken-symmetry states intertwined with superconductivity. Recent resonant soft X-ray scattering experiments report commensurate 3a0 charge density wave order in infinite-layer nickelates, which has important implications regarding the universal interplay between charge order and superconductivity in both cuprates and nickelates. Here we present X-ray scattering and spectroscopy measurements on a series of NdNiO2+x samples, which reveal that the signatures of charge density wave order are absent in fully reduced, single-phase NdNiO2. The 3a0 superlattice peak instead originates from a partially reduced impurity phase where excess apical oxygens form ordered rows with three-unit-cell periodicity. The absence of any observable charge density wave order in NdNiO2 highlights a crucial difference between the phase diagrams of cuprate and nickelate superconductors.
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Grants
- DE-SC0019414 U.S. Department of Energy (DOE)
- DE-AC02-05CH11231 U.S. Department of Energy (DOE)
- DE-AC02-06CH11357 U.S. Department of Energy (DOE)
- FA9550-21-1-0168 United States Department of Defense | United States Air Force | AFMC | Air Force Office of Scientific Research (AF Office of Scientific Research)
- DMR-2104427 National Science Foundation (NSF)
- NNCI-2025233 National Science Foundation (NSF)
- GBMF3850 Gordon and Betty Moore Foundation (Gordon E. and Betty I. Moore Foundation)
- GBMF9073 Gordon and Betty Moore Foundation (Gordon E. and Betty I. Moore Foundation)
- Part of the research described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), the Natural Sciences and Engineering Research Council (NSERC), the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan.
- The microscopy work at Cornell was supported by the NSF PARADIM, with additional support from Cornell University, the Weill Institute, the Kavli Institute at Cornell, and the Packard Foundation.
- G.H. acknowledges support from Severo Ochoa FUNFUTURE (No. CEX2019-000917-S) of the Spanish Ministry of Science and Innovation and by the Generalitat de Catalunya (2021 SGR 00445).
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Affiliation(s)
- C T Parzyck
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
| | - N K Gupta
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - Y Wu
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
| | - V Anil
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
| | - L Bhatt
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - M Bouliane
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - R Gong
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - B Z Gregory
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - A Luo
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - R Sutarto
- Canadian Light Source, Saskatoon, Saskatchewan, Canada
| | - F He
- Canadian Light Source, Saskatoon, Saskatchewan, Canada
| | - Y-D Chuang
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - T Zhou
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, IL, USA
| | - G Herranz
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Bellaterra, Spain
| | - L F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA
| | - A Singer
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA
- Leibniz-Institut für Kristallzüchtung, Berlin, Germany
| | - D G Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - K M Shen
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA.
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Bellaterra, Spain.
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA.
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2
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Parzyck CT, Gupta NK, Wu Y, Anil V, Bhatt L, Bouliane M, Gong R, Gregory BZ, Luo A, Sutarto R, He F, Chuang YD, Zhou T, Herranz G, Kourkoutis LF, Singer A, Schlom DG, Hawthorn DG, Shen KM. Publisher Correction: Absence of 3a 0 charge density wave order in the infinite-layer nickelate NdNiO 2. Nat Mater 2024; 23:440. [PMID: 38347120 PMCID: PMC10917676 DOI: 10.1038/s41563-024-01832-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Affiliation(s)
- C T Parzyck
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
| | - N K Gupta
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - Y Wu
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
| | - V Anil
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
| | - L Bhatt
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - M Bouliane
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - R Gong
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - B Z Gregory
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - A Luo
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - R Sutarto
- Canadian Light Source, Saskatoon, Saskatchewan, Canada
| | - F He
- Canadian Light Source, Saskatoon, Saskatchewan, Canada
| | - Y-D Chuang
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - T Zhou
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, IL, USA
| | - G Herranz
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Bellaterra, Spain
| | - L F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA
| | - A Singer
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA
- Leibniz-Institut für Kristallzüchtung, Berlin, Germany
| | - D G Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - K M Shen
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, NY, USA.
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Bellaterra, Spain.
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA.
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3
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Hepting M, Bejas M, Nag A, Yamase H, Coppola N, Betto D, Falter C, Garcia-Fernandez M, Agrestini S, Zhou KJ, Minola M, Sacco C, Maritato L, Orgiani P, Wei HI, Shen KM, Schlom DG, Galdi A, Greco A, Keimer B. Gapped Collective Charge Excitations and Interlayer Hopping in Cuprate Superconductors. Phys Rev Lett 2022; 129:047001. [PMID: 35938998 DOI: 10.1103/physrevlett.129.047001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 03/29/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
We use resonant inelastic x-ray scattering to probe the propagation of plasmons in the electron-doped cuprate superconductor Sr_{0.9}La_{0.1}CuO_{2}. We detect a plasmon gap of ∼120 meV at the two-dimensional Brillouin zone center, indicating that low-energy plasmons in Sr_{0.9}La_{0.1}CuO_{2} are not strictly acoustic. The plasmon dispersion, including the gap, is accurately captured by layered t-J-V model calculations. A similar analysis performed on recent resonant inelastic x-ray scattering data from other cuprates suggests that the plasmon gap is generic and its size is related to the magnitude of the interlayer hopping t_{z}. Our work signifies the three dimensionality of the charge dynamics in layered cuprates and provides a new method to determine t_{z}.
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Affiliation(s)
- M Hepting
- Max-Planck-Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - M Bejas
- Facultad de Ciencias Exactas, Ingeniería y Agrimensura and Instituto de Física de Rosario (UNR-CONICET), Avenida Pellegrini 250, 2000 Rosario, Argentina
| | - A Nag
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, United Kingdom
| | - H Yamase
- International Center of Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0047, Japan
- Department of Condensed Matter Physics, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - N Coppola
- Dipartimento di Ingegneria Industriale, Università di Salerno, I-84084 Fisciano (Salerno), Italy
| | - D Betto
- Max-Planck-Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - C Falter
- Institut für Festkörpertheorie, Westfälische Wilhelms-Universität, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany
| | | | - S Agrestini
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, United Kingdom
| | - Ke-Jin Zhou
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, United Kingdom
| | - M Minola
- Max-Planck-Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - C Sacco
- Dipartimento di Ingegneria Industriale, Università di Salerno, I-84084 Fisciano (Salerno), Italy
| | - L Maritato
- Dipartimento di Ingegneria Industriale, Università di Salerno, I-84084 Fisciano (Salerno), Italy
- CNR-SPIN Salerno, Università di Salerno, I-84084 Fisciano (Salerno), Italy
| | - P Orgiani
- CNR-SPIN Salerno, Università di Salerno, I-84084 Fisciano (Salerno), Italy
- CNR-IOM, TASC Laboratory in Area Science Park, 34139 Trieste, Italy
| | - H I Wei
- LASSP, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - K M Shen
- LASSP, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
- Leibniz-Institut für Kristallzüchtung, Max-Born-Straße 2, 12489 Berlin, Germany
| | - A Galdi
- Dipartimento di Ingegneria Industriale, Università di Salerno, I-84084 Fisciano (Salerno), Italy
- Cornell Laboratory for Accelerator Based Sciences and Education, Cornell University, Ithaca, New York 14853, USA
| | - A Greco
- Facultad de Ciencias Exactas, Ingeniería y Agrimensura and Instituto de Física de Rosario (UNR-CONICET), Avenida Pellegrini 250, 2000 Rosario, Argentina
| | - B Keimer
- Max-Planck-Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
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4
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Parzyck CT, Galdi A, Nangoi JK, DeBenedetti WJI, Balajka J, Faeth BD, Paik H, Hu C, Arias TA, Hines MA, Schlom DG, Shen KM, Maxson JM. Single-Crystal Alkali Antimonide Photocathodes: High Efficiency in the Ultrathin Limit. Phys Rev Lett 2022; 128:114801. [PMID: 35363005 DOI: 10.1103/physrevlett.128.114801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
The properties of photoemission electron sources determine the ultimate performance of a wide class of electron accelerators and photon detectors. To date, all high-efficiency visible-light photocathode materials are either polycrystalline or exhibit intrinsic surface disorder, both of which limit emitted electron beam brightness. In this Letter, we demonstrate the synthesis of epitaxial thin films of Cs_{3}Sb on 3C-SiC (001) using molecular-beam epitaxy. Films as thin as 4 nm have quantum efficiencies exceeding 2% at 532 nm. We also find that epitaxial films have an order of magnitude larger quantum efficiency at 650 nm than comparable polycrystalline films on Si. Additionally, these films permit angle-resolved photoemission spectroscopy measurements of the electronic structure, which are found to be in good agreement with theory. Epitaxial films open the door to dramatic brightness enhancements via increased efficiency near threshold, reduced surface disorder, and the possibility of engineering new photoemission functionality at the level of single atomic layers.
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Affiliation(s)
- C T Parzyck
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - A Galdi
- Cornell Laboratory for Accelerator-Based Sciences and Education, Cornell University, Ithaca, New York 14853, USA
| | - J K Nangoi
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - W J I DeBenedetti
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - J Balajka
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - B D Faeth
- Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), Cornell University, Ithaca, New York 14853, USA
| | - H Paik
- Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM), Cornell University, Ithaca, New York 14853, USA
| | - C Hu
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - T A Arias
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - M A Hines
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA
- Leibniz-Institut für Kristallzüchtung, Max-Born-Straße 2, 12489 Berlin, Germany
| | - K M Shen
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA
| | - J M Maxson
- Cornell Laboratory for Accelerator-Based Sciences and Education, Cornell University, Ithaca, New York 14853, USA
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5
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Ruf JP, Paik H, Schreiber NJ, Nair HP, Miao L, Kawasaki JK, Nelson JN, Faeth BD, Lee Y, Goodge BH, Pamuk B, Fennie CJ, Kourkoutis LF, Schlom DG, Shen KM. Strain-stabilized superconductivity. Nat Commun 2021; 12:59. [PMID: 33397949 PMCID: PMC7782483 DOI: 10.1038/s41467-020-20252-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/19/2020] [Indexed: 11/09/2022] Open
Abstract
Superconductivity is among the most fascinating and well-studied quantum states of matter. Despite over 100 years of research, a detailed understanding of how features of the normal-state electronic structure determine superconducting properties has remained elusive. For instance, the ability to deterministically enhance the superconducting transition temperature by design, rather than by serendipity, has been a long sought-after goal in condensed matter physics and materials science, but achieving this objective may require new tools, techniques and approaches. Here, we report the transmutation of a normal metal into a superconductor through the application of epitaxial strain. We demonstrate that synthesizing RuO2 thin films on (110)-oriented TiO2 substrates enhances the density of states near the Fermi level, which stabilizes superconductivity under strain, and suggests that a promising strategy to create new transition-metal superconductors is to apply judiciously chosen anisotropic strains that redistribute carriers within the low-energy manifold of d orbitals.
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Affiliation(s)
- J P Ruf
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA.
| | - H Paik
- Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials, Cornell University, Ithaca, NY, 14853, USA.,Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - N J Schreiber
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - H P Nair
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - L Miao
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA
| | - J K Kawasaki
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA.,Department of Materials Science and Engineering, University of Wisconsin, Madison, WI, 53706, USA
| | - J N Nelson
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA
| | - B D Faeth
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA.,Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials, Cornell University, Ithaca, NY, 14853, USA
| | - Y Lee
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA
| | - B H Goodge
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA
| | - B Pamuk
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, 14853, USA
| | - C J Fennie
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, 14853, USA
| | - L F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA.,Leibniz-Institut für Kristallzüchtung, Max-Born-Str. 2, Berlin, 12489, Germany
| | - K M Shen
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA. .,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA.
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6
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Wang Y, Bossé G, Nair HP, Schreiber NJ, Ruf JP, Cheng B, Adamo C, Shai DE, Lubashevsky Y, Schlom DG, Shen KM, Armitage NP. Subterahertz Momentum Drag and Violation of Matthiessen's Rule in an Ultraclean Ferromagnetic SrRuO_{3} Metallic Thin Film. Phys Rev Lett 2020; 125:217401. [PMID: 33274990 DOI: 10.1103/physrevlett.125.217401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 08/14/2020] [Accepted: 10/09/2020] [Indexed: 06/12/2023]
Abstract
SrRuO_{3}, a ferromagnet with an approximately 160 K Curie temperature, exhibits a T^{2}-dependent dc resistivity below ≈30 K. Nevertheless, previous optical studies in the infrared and terahertz range show non-Drude dynamics at low temperatures, which seem to contradict Fermi-liquid predictions. In this work, we measure the low-frequency THz range response of thin films with residual resistivity ratios, ρ_{300K}/ρ_{4K}≈74. At temperatures below 30 K, we find both a sharp zero frequency mode which has a width narrower than k_{B}T/ℏ as well as a broader zero frequency Lorentzian that has at least an order of magnitude larger scattering. Both features have temperature dependences consistent with a Fermi liquid with the wider feature explicitly showing a T^{2} scaling. Above 30 K, there is a crossover to a regime described by a single Drude peak that we believe arises from strong interband electron-electron scattering. Such two channel Drude transport sheds light on reports of the violation of Matthiessen's rule and extreme sensitivity to disorder in metallic ruthenates.
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Affiliation(s)
- Youcheng Wang
- The Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - G Bossé
- The Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
- Physics Department, University of North Florida, Jacksonville, Florida 32224-7699, USA
| | - H P Nair
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - N J Schreiber
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - J P Ruf
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - B Cheng
- The Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - C Adamo
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - D E Shai
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Y Lubashevsky
- The Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - K M Shen
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - N P Armitage
- The Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
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7
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Nelson JN, Parzyck CT, Faeth BD, Kawasaki JK, Schlom DG, Shen KM. Mott gap collapse in lightly hole-doped Sr 2-xK xIrO 4. Nat Commun 2020; 11:2597. [PMID: 32444617 PMCID: PMC7244596 DOI: 10.1038/s41467-020-16425-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 04/23/2020] [Indexed: 11/09/2022] Open
Abstract
The evolution of Sr2IrO4 upon carrier doping has been a subject of intense interest, due to its similarities to the parent cuprates, yet the intrinsic behaviour of Sr2IrO4 upon hole doping remains enigmatic. Here, we synthesize and investigate hole-doped Sr2-xKxIrO4 utilizing a combination of reactive oxide molecular-beam epitaxy, substitutional diffusion and in-situ angle-resolved photoemission spectroscopy. Upon hole doping, we observe the formation of a coherent, two-band Fermi surface, consisting of both hole pockets centred at (π, 0) and electron pockets centred at (π/2, π/2). In particular, the strong similarities between the Fermi surface topology and quasiparticle band structure of hole- and electron-doped Sr2IrO4 are striking given the different internal structure of doped electrons versus holes.
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Affiliation(s)
- J N Nelson
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York, 14853, USA
| | - C T Parzyck
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York, 14853, USA
| | - B D Faeth
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York, 14853, USA
| | - J K Kawasaki
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York, 14853, USA.,Department of Materials Science and Engineering, Cornell University, Ithaca, New York, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York, 14853, USA.,Department of Materials Science and Engineering, University of Wisconsin, Madison, Wisconsin, 53706, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York, 14853, USA
| | - K M Shen
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York, 14853, USA. .,Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York, 14853, USA.
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8
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Ivashko O, Horio M, Wan W, Christensen NB, McNally DE, Paris E, Tseng Y, Shaik NE, Rønnow HM, Wei HI, Adamo C, Lichtensteiger C, Gibert M, Beasley MR, Shen KM, Tomczak JM, Schmitt T, Chang J. Strain-engineering Mott-insulating La 2CuO 4. Nat Commun 2019; 10:786. [PMID: 30783084 PMCID: PMC6381167 DOI: 10.1038/s41467-019-08664-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/20/2019] [Indexed: 11/10/2022] Open
Abstract
The transition temperature Tc of unconventional superconductivity is often tunable. For a monolayer of FeSe, for example, the sweet spot is uniquely bound to titanium-oxide substrates. By contrast for La2-xSrxCuO4 thin films, such substrates are sub-optimal and the highest Tc is instead obtained using LaSrAlO4. An outstanding challenge is thus to understand the optimal conditions for superconductivity in thin films: which microscopic parameters drive the change in Tc and how can we tune them? Here we demonstrate, by a combination of x-ray absorption and resonant inelastic x-ray scattering spectroscopy, how the Coulomb and magnetic-exchange interaction of La2CuO4 thin films can be enhanced by compressive strain. Our experiments and theoretical calculations establish that the substrate producing the largest Tc under doping also generates the largest nearest neighbour hopping integral, Coulomb and magnetic-exchange interaction. We hence suggest optimising the parent Mott state as a strategy for enhancing the superconducting transition temperature in cuprates.
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Affiliation(s)
- O Ivashko
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland.
| | - M Horio
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - W Wan
- Department of Physics, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - N B Christensen
- Department of Physics, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - D E McNally
- Photon Science Division, Swiss Light Source, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - E Paris
- Photon Science Division, Swiss Light Source, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Y Tseng
- Photon Science Division, Swiss Light Source, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - N E Shaik
- Institute of Physics, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - H M Rønnow
- Institute of Physics, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - H I Wei
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA
| | - C Adamo
- Department of Applied Physics, Stanford University, Stanford, CA, 94305, USA
| | - C Lichtensteiger
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest Ansermet, 1211, Geneva, Switzerland
| | - M Gibert
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - M R Beasley
- Department of Applied Physics, Stanford University, Stanford, CA, 94305, USA
| | - K M Shen
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY, 14853, USA
| | - J M Tomczak
- Institute of Solid State Physics, Vienna University of Technology, A-1040, Vienna, Austria
| | - T Schmitt
- Photon Science Division, Swiss Light Source, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - J Chang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
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9
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Burganov B, Adamo C, Mulder A, Uchida M, King PDC, Harter JW, Shai DE, Gibbs AS, Mackenzie AP, Uecker R, Bruetzam M, Beasley MR, Fennie CJ, Schlom DG, Shen KM. Strain Control of Fermiology and Many-Body Interactions in Two-Dimensional Ruthenates. Phys Rev Lett 2016; 116:197003. [PMID: 27232037 DOI: 10.1103/physrevlett.116.197003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Indexed: 06/05/2023]
Abstract
Here we demonstrate how the Fermi surface topology and quantum many-body interactions can be manipulated via epitaxial strain in the spin-triplet superconductor Sr_{2}RuO_{4} and its isoelectronic counterpart Ba_{2}RuO_{4} using oxide molecular beam epitaxy, in situ angle-resolved photoemission spectroscopy, and transport measurements. Near the topological transition of the γ Fermi surface sheet, we observe clear signatures of critical fluctuations, while the quasiparticle mass enhancement is found to increase rapidly and monotonically with increasing Ru-O bond distance. Our work demonstrates the possibilities for using epitaxial strain as a disorder-free means of manipulating emergent properties, many-body interactions, and potentially the superconductivity in correlated materials.
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Affiliation(s)
- B Burganov
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - C Adamo
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
| | - A Mulder
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
| | - M Uchida
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - P D C King
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
- School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, United Kingdom
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - J W Harter
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - D E Shai
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - A S Gibbs
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
| | - A P Mackenzie
- School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, United Kingdom
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - R Uecker
- Leibniz Institute for Crystal Growth, D-12489 Berlin, Germany
| | - M Bruetzam
- Leibniz Institute for Crystal Growth, D-12489 Berlin, Germany
| | - M R Beasley
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
| | - C J Fennie
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - K M Shen
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
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10
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Nie YF, Di Sante D, Chatterjee S, King PDC, Uchida M, Ciuchi S, Schlom DG, Shen KM. Formation and Observation of a Quasi-Two-Dimensional dxy Electron Liquid in Epitaxially Stabilized Sr(2-x)La(x)TiO4 Thin Films. Phys Rev Lett 2015; 115:096405. [PMID: 26371669 DOI: 10.1103/physrevlett.115.096405] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Indexed: 06/05/2023]
Abstract
We report the formation and observation of an electron liquid in Sr(2-x)La(x)TiO4, the quasi-two-dimensional counterpart of SrTiO3, through reactive molecular-beam epitaxy and in situ angle-resolved photoemission spectroscopy. The lowest lying states are found to be comprised of Ti 3d_{xy} orbitals, analogous to the LaAlO3/SrTiO3 interface and exhibit unusually broad features characterized by quantized energy levels and a reduced Luttinger volume. Using model calculations, we explain these characteristics through an interplay of disorder and electron-phonon coupling acting cooperatively at similar energy scales, which provides a possible mechanism for explaining the low free carrier concentrations observed at various oxide heterostructures such as the LaAlO3/SrTiO3 interface.
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Affiliation(s)
- Y F Nie
- National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - D Di Sante
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, Coppito, L'Aquila I-67100, Italy
- CNR-SPIN, Via Vetoio, L'Aquila I-67100, Italy
| | - S Chatterjee
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - P D C King
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - M Uchida
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - S Ciuchi
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, Coppito, L'Aquila I-67100, Italy
- CNR-ISC, Via dei Taurini, Rome I-00185, Italy
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - K M Shen
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
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11
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Nie YF, King PDC, Kim CH, Uchida M, Wei HI, Faeth BD, Ruf JP, Ruff JPC, Xie L, Pan X, Fennie CJ, Schlom DG, Shen KM. Interplay of spin-orbit interactions, dimensionality, and octahedral rotations in semimetallic SrIrO(3). Phys Rev Lett 2015; 114:016401. [PMID: 25615483 DOI: 10.1103/physrevlett.114.016401] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Indexed: 06/04/2023]
Abstract
We employ reactive molecular-beam epitaxy to synthesize the metastable perovskite SrIrO(3) and utilize in situ angle-resolved photoemission to reveal its electronic structure as an exotic narrow-band semimetal. We discover remarkably narrow bands which originate from a confluence of strong spin-orbit interactions, dimensionality, and both in- and out-of-plane IrO(6) octahedral rotations. The partial occupation of numerous bands with strongly mixed orbital characters signals the breakdown of the single-band Mott picture that characterizes its insulating two-dimensional counterpart, Sr(2)IrO(4), illustrating the power of structure-property relations for manipulating the subtle balance between spin-orbit interactions and electron-electron interactions.
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Affiliation(s)
- Y F Nie
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA and Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA and National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - P D C King
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA and Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - C H Kim
- Department of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
| | - M Uchida
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - H I Wei
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - B D Faeth
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - J P Ruf
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - J P C Ruff
- CHESS, Cornell University, Ithaca, New York 14853, USA
| | - L Xie
- National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China and Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - X Pan
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - C J Fennie
- Department of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
| | - D G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA and Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
| | - K M Shen
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA and Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA
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12
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Nie YF, Zhu Y, Lee CH, Kourkoutis LF, Mundy JA, Junquera J, Ghosez P, Baek DJ, Sung S, Xi XX, Shen KM, Muller DA, Schlom DG. Atomically precise interfaces from non-stoichiometric deposition. Nat Commun 2014; 5:4530. [DOI: 10.1038/ncomms5530] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 06/27/2014] [Indexed: 11/09/2022] Open
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13
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King PDC, Wei HI, Nie YF, Uchida M, Adamo C, Zhu S, He X, Božović I, Schlom DG, Shen KM. Atomic-scale control of competing electronic phases in ultrathin LaNiO₃. Nat Nanotechnol 2014; 9:443-7. [PMID: 24705511 DOI: 10.1038/nnano.2014.59] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 02/21/2014] [Indexed: 05/27/2023]
Abstract
In an effort to scale down electronic devices to atomic dimensions, the use of transition-metal oxides may provide advantages over conventional semiconductors. Their high carrier densities and short electronic length scales are desirable for miniaturization, while strong interactions that mediate exotic phase diagrams open new avenues for engineering emergent properties. Nevertheless, understanding how their correlated electronic states can be manipulated at the nanoscale remains challenging. Here, we use angle-resolved photoemission spectroscopy to uncover an abrupt destruction of Fermi liquid-like quasiparticles in the correlated metal LaNiO₃ when confined to a critical film thickness of two unit cells. This is accompanied by the onset of an insulating phase as measured by electrical transport. We show how this is driven by an instability to an incipient order of the underlying quantum many-body system, demonstrating the power of artificial confinement to harness control over competing phases in complex oxides with atomic-scale precision.
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Affiliation(s)
- P D C King
- 1] Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA [2] Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - H I Wei
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Y F Nie
- 1] Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA [2] Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - M Uchida
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - C Adamo
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - S Zhu
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - X He
- Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - I Božović
- Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - D G Schlom
- 1] Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA [2] Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - K M Shen
- 1] Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA [2] Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
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14
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Eknapakul T, King PDC, Asakawa M, Buaphet P, He RH, Mo SK, Takagi H, Shen KM, Baumberger F, Sasagawa T, Jungthawan S, Meevasana W. Electronic structure of a quasi-freestanding MoS₂ monolayer. Nano Lett 2014; 14:1312-6. [PMID: 24552197 DOI: 10.1021/nl4042824] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Several transition-metal dichalcogenides exhibit a striking crossover from indirect to direct band gap semiconductors as they are thinned down to a single monolayer. Here, we demonstrate how an electronic structure characteristic of the isolated monolayer can be created at the surface of a bulk MoS2 crystal. This is achieved by intercalating potassium in the interlayer van der Waals gap, expanding its size while simultaneously doping electrons into the conduction band. Our angle-resolved photoemission measurements reveal resulting electron pockets centered at the K̅ and K' points of the Brillouin zone, providing the first momentum-resolved measurements of how the conduction band dispersions evolve to yield an approximately direct band gap of ∼1.8 eV in quasi-freestanding monolayer MoS2. As well as validating previous theoretical proposals, this establishes a novel methodology for manipulating electronic structure in transition-metal dichalcogenides, opening a new route for the generation of large-area quasi-freestanding monolayers for future fundamental study and use in practical applications.
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Affiliation(s)
- T Eknapakul
- School of Physics, Suranaree University of Technology , Nakhon Ratchasima, 30000, Thailand
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15
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Arpino KE, Wallace DC, Nie YF, Birol T, King PDC, Chatterjee S, Uchida M, Koohpayeh SM, Wen JJ, Page K, Fennie CJ, Shen KM, McQueen TM. Evidence for topologically protected surface states and a superconducting phase in [Tl4](Tl(1-x)Sn(x))Te3 using photoemission, specific heat, and magnetization measurements, and density functional theory. Phys Rev Lett 2014; 112:017002. [PMID: 24483920 DOI: 10.1103/physrevlett.112.017002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Indexed: 05/22/2023]
Abstract
We report the discovery of surface states in the perovskite superconductor [Tl4]TlTe3 (Tl5Te3) and its nonsuperconducting tin-doped derivative [Tl4](Tl0.4Sn0.6)Te3 as observed by angle-resolved photoemission spectroscopy. Density functional theory calculations predict that the surface states are protected by a Z2 topology of the bulk band structure. Specific heat and magnetization measurements show that Tl5Te3 has a superconducting volume fraction in excess of 95%. Thus Tl5Te3 is an ideal material in which to study the interplay of bulk band topology and superconductivity.
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Affiliation(s)
- K E Arpino
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA and Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - D C Wallace
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA and Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Y F Nie
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA and Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
| | - T Birol
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
| | - P D C King
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA
| | - S Chatterjee
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - M Uchida
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
| | - S M Koohpayeh
- Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - J-J Wen
- Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - K Page
- Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - C J Fennie
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
| | - K M Shen
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA
| | - T M McQueen
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA and Institute for Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA
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16
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Shai DE, Adamo C, Shen DW, Brooks CM, Harter JW, Monkman EJ, Burganov B, Schlom DG, Shen KM. Quasiparticle mass enhancement and temperature dependence of the electronic structure of ferromagnetic SrRuO3 thin films. Phys Rev Lett 2013; 110:087004. [PMID: 23473191 DOI: 10.1103/physrevlett.110.087004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Indexed: 06/01/2023]
Abstract
We report high-resolution angle-resolved photoemission studies of epitaxial thin films of the correlated 4d transition metal oxide ferromagnet SrRuO(3). The Fermi surface in the ferromagnetic state consists of well-defined Landau quasiparticles exhibiting strong coupling to low-energy bosonic modes which contributes to the large effective masses observed by transport and thermodynamic measurements. Upon warming the material through its Curie temperature, we observe a substantial decrease in quasiparticle coherence but negligible changes in the ferromagnetic exchange splitting, suggesting that local moments play an important role in the ferromagnetism in SrRuO(3).
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Affiliation(s)
- D E Shai
- Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA
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17
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Shai DE, Melville AJ, Harter JW, Monkman EJ, Shen DW, Schmehl A, Schlom DG, Shen KM. Temperature dependence of the electronic structure and Fermi-surface reconstruction of Eu(1-x)Gd(x)O through the ferromagnetic metal-insulator transition. Phys Rev Lett 2012; 108:267003. [PMID: 23005009 DOI: 10.1103/physrevlett.108.267003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Indexed: 06/01/2023]
Abstract
We present angle-resolved photoemission spectroscopy of Eu(1-x)Gd(x)O through the ferromagnetic metal-insulator transition. In the ferromagnetic phase, we observe Fermi surface pockets at the Brillouin zone boundary, consistent with density functional theory, which predicts a half-metal. Upon warming into the paramagnetic state, our results reveal a strong momentum-dependent evolution of the electronic structure, where the metallic states at the zone boundary are replaced by pseudogapped states at the Brillouin zone center due to the absence of magnetic long-range order of the Eu 4f moments.
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Affiliation(s)
- D E Shai
- Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA
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18
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Achkar AJ, Regier TZ, Monkman EJ, Shen KM, Hawthorn DG. Determination of total x-ray absorption coefficient using non-resonant x-ray emission. Sci Rep 2011; 1:182. [PMID: 22355697 PMCID: PMC3240986 DOI: 10.1038/srep00182] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 11/22/2011] [Indexed: 11/09/2022] Open
Abstract
An alternative measure of x-ray absorption spectroscopy (XAS) called inverse partial fluorescence yield (IPFY) has recently been developed that is both bulk sensitive and free of saturation effects. Here we show that the angle dependence of IPFY can provide a measure directly proportional to the total x-ray absorption coefficient, µ(E). In contrast, fluorescence yield (FY) and electron yield (EY) spectra are offset and/or distorted from µ(E) by an unknown and difficult to measure amount. Moreover, our measurement can determine µ(E) in absolute units with no free parameters by scaling to µ(E) at the non-resonant emission energy. We demonstrate this technique with measurements on NiO and NdGaO3. Determining µ(E) across edge-steps enables the use of XAS as a non-destructive measure of material composition. In NdGaO3, we also demonstrate the utility of IPFY for insulating samples, where neither EY or FY provide reliable spectra due to sample charging and self-absorption effects, respectively.
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Affiliation(s)
- A J Achkar
- Department of Physics and Astronomy, University of Waterloo, Waterloo, N2L 3G1, Canada
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19
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Hawthorn DG, He F, Venema L, Davis H, Achkar AJ, Zhang J, Sutarto R, Wadati H, Radi A, Wilson T, Wright G, Shen KM, Geck J, Zhang H, Novák V, Sawatzky GA. An in-vacuum diffractometer for resonant elastic soft x-ray scattering. Rev Sci Instrum 2011; 82:073104. [PMID: 21806169 DOI: 10.1063/1.3607438] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We describe the design, construction, and performance of a 4-circle in-vacuum diffractometer for resonant elastic soft x-ray scattering. The diffractometer, installed on the resonant elastic and inelastic x-ray scattering beamline at the Canadian Light Source, includes 9 in-vacuum motions driven by in-vacuum stepper motors and operates in ultra-high vacuum at base pressure of 2 × 10(-10) Torr. Cooling to a base temperature of 18 K is provided with a closed-cycle cryostat. The diffractometer includes a choice of 3 photon detectors: a photodiode, a channeltron, and a 2D sensitive channelplate detector. Along with variable slit and filter options, these detectors are suitable for studying a wide range of phenomena having both weak and strong diffraction signals. Example measurements of diffraction and reflectivity in Nd-doped (La,Sr)(2)CuO(4) and thin film (Ga,Mn)As are shown.
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Affiliation(s)
- D G Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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20
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King PDC, Rosen JA, Meevasana W, Tamai A, Rozbicki E, Comin R, Levy G, Fournier D, Yoshida Y, Eisaki H, Shen KM, Ingle NJC, Damascelli A, Baumberger F. Structural origin of apparent Fermi surface pockets in angle-resolved photoemission of Bi₂Sr(2-x)La(x)CuO(6+δ). Phys Rev Lett 2011; 106:127005. [PMID: 21517346 DOI: 10.1103/physrevlett.106.127005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Indexed: 05/30/2023]
Abstract
We observe apparent hole pockets in the Fermi surfaces of single-layer Bi-based cuprate superconductors from angle-resolved photoemission. From detailed low-energy electron diffraction measurements and an analysis of the angle-resolved photoemission polarization dependence, we show that these pockets are not intrinsic but arise from multiple overlapping superstructure replicas of the main and shadow bands. We further demonstrate that the hole pockets reported recently from angle-resolved photoemission [Meng et al., Nature (London) 462, 335 (2009)] have a similar structural origin and are inconsistent with an intrinsic hole pocket associated with the electronic structure of a doped CuO₂ plane.
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Affiliation(s)
- P D C King
- School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS, United Kingdom
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21
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Mairoser T, Schmehl A, Melville A, Heeg T, Canella L, Böni P, Zander W, Schubert J, Shai DE, Monkman EJ, Shen KM, Schlom DG, Mannhart J. Is there an intrinsic limit to the charge-carrier-induced increase of the Curie temperature of EuO? Phys Rev Lett 2010; 105:257206. [PMID: 21231624 DOI: 10.1103/physrevlett.105.257206] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Indexed: 05/30/2023]
Abstract
Rare earth doping is the key strategy to increase the Curie temperature (T(C)) of the ferromagnetic semiconductor EuO. The interplay between doping and charge carrier density (n), and the limit of the T(C) increase, however, are yet to be understood. We report measurements of n and T(C) of Gd-doped EuO over a wide range of doping levels. The results show a direct correlation between n and T(C), with both exhibiting a maximum at high doping. On average, less than 35% of the dopants act as donors, raising the question about the limit to increasing T(C).
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Affiliation(s)
- T Mairoser
- Zentrum für elektronische Korrelation und Magnetismus, Universität Augsburg, Universitätsstrasse 1, 86159 Augsburg, Germany
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22
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Peets DC, Hawthorn DG, Shen KM, Kim YJ, Ellis DS, Zhang H, Komiya S, Ando Y, Sawatzky GA, Liang R, Bonn DA, Hardy WN. X-ray absorption spectra reveal the inapplicability of the single-band Hubbard model to overdoped cuprate superconductors. Phys Rev Lett 2009; 103:087402. [PMID: 19792760 DOI: 10.1103/physrevlett.103.087402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Indexed: 05/28/2023]
Abstract
X-ray absorption spectra on the overdoped high-temperature superconductors Tl2Ba2CuO(6+delta) and La(2-x)SrxCuO(4+/-delta) reveal a striking departure in the electronic structure from that of the underdoped regime. The upper Hubbard band, identified with strong correlation effects, is not observed on the oxygen K edge, while the lowest-energy prepeak gains less intensity than expected above p approximately 0.21. This suggests a breakdown of the Zhang-Rice singlet approximation and a loss of correlation effects or a significant shift in the most fundamental parameters of the system, rendering single-band Hubbard models inapplicable. Such fundamental changes suggest that the overdoped regime may offer a distinct route to understanding in the cuprates.
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Affiliation(s)
- D C Peets
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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23
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Shen KM, Kikugawa N, Bergemann C, Balicas L, Baumberger F, Meevasana W, Ingle NJC, Maeno Y, Shen ZX, Mackenzie AP. Evolution of the Fermi surface and quasiparticle renormalization through a van Hove singularity in Sr2-yLayRuO4. Phys Rev Lett 2007; 99:187001. [PMID: 17995427 DOI: 10.1103/physrevlett.99.187001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Indexed: 05/25/2023]
Abstract
We employ a combination of chemical substitution and angle resolved photoemission spectroscopy to prove that the Fermi level in the gamma band of Sr(2-y)La(y)RuO(4) can be made to traverse a van Hove singularity. Remarkably, the large mass renormalization has little dependence on either k or doping. By combining the results from photoemission with thermodynamic measurements on the same batches of crystals, we deduce a parametrization of the full many-body quasiparticle dispersion in Sr(2)RuO(4) which extends from the Fermi level to approximately 20 meV above it.
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Affiliation(s)
- K M Shen
- Department of Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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24
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Baumberger F, Ingle NJC, Meevasana W, Shen KM, Lu DH, Perry RS, Mackenzie AP, Hussain Z, Singh DJ, Shen ZX. Fermi surface and quasiparticle excitations of Sr2RhO4. Phys Rev Lett 2006; 96:246402. [PMID: 16907260 DOI: 10.1103/physrevlett.96.246402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2005] [Indexed: 05/11/2023]
Abstract
The electronic structure of the layered 4d transition metal oxide Sr2RhO4 is investigated by angle resolved photoemission. We find well-defined quasiparticle excitations with a highly anisotropic dispersion, suggesting a quasi-two-dimensional Fermi-liquid-like ground state. Markedly different from the isostructural Sr2RuO4, only two bands with dominant Rh 4dxz,zy character contribute to the Fermi surface. A quantitative analysis of the photoemission quasiparticle band structure is in excellent agreement with bulk data. In contrast, it is found that state-of-the-art density functional calculations in the local density approximation differ significantly from the experimental findings.
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Affiliation(s)
- F Baumberger
- Department of Applied Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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25
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Meevasana W, Ingle NJC, Lu DH, Shi JR, Baumberger F, Shen KM, Lee WS, Cuk T, Eisaki H, Devereaux TP, Nagaosa N, Zaanen J, Shen ZX. Doping dependence of the coupling of electrons to bosonic modes in the single-layer high-temperature Bi2Sr2CuO6 superconductor. Phys Rev Lett 2006; 96:157003. [PMID: 16712188 DOI: 10.1103/physrevlett.96.157003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Indexed: 05/09/2023]
Abstract
A recent highlight in the study of high-T(c) superconductors is the observation of band renormalization or self-energy effects on the quasiparticles. This is seen in the form of kinks in the quasiparticle dispersions as measured by photoemission and interpreted as signatures of collective bosonic modes coupling to the electrons. Here we compare for the first time the self-energies in an optimally doped and strongly overdoped, nonsuperconducting single-layer Bi-cuprate (Bi2Sr2CuO6). In addition to the appearance of a strong overall weakening, we also find that the weight of the self-energy in the overdoped system shifts to higher energies. We present evidence that this is related to a change in the coupling to c-axis phonons due to the rapid change of the c-axis screening in this doping range.
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Affiliation(s)
- W Meevasana
- Department of Physics, Applied Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA.
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26
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Baumberger F, Ingle NJC, Kikugawa N, Hossain MA, Meevasana W, Perry RS, Shen KM, Lu DH, Damascelli A, Rost A, Mackenzie AP, Hussain Z, Shen ZX. Nested fermi surface and electronic instability in Ca3Ru2O7. Phys Rev Lett 2006; 96:107601. [PMID: 16605788 DOI: 10.1103/physrevlett.96.107601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Indexed: 05/08/2023]
Abstract
High-resolution angular resolved photoemission data reveal well-defined quasiparticle bands of unusually low weight, emerging in line with the metallic phase of Ca(3)Ru(2)O(7) below approximately 30 K . At the bulk structural phase transition temperature of 48 K, we find clear evidence for an electronic instability, gapping large parts of the underlying Fermi surface that appears to be nested. Metallic pockets are found to survive in the small, non-nested sections, constituting a low-temperature Fermi surface with 2 orders of magnitude smaller volume than in all other metallic ruthenates. The Fermi velocities and volumes of these pockets are in agreement with the results of complementary quantum oscillation measurements on the same crystal batches.
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Affiliation(s)
- F Baumberger
- Department of Applied Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, California 94305, USA
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27
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Shen KM, Ronning F, Lu DH, Lee WS, Ingle NJC, Meevasana W, Baumberger F, Damascelli A, Armitage NP, Miller LL, Kohsaka Y, Azuma M, Takano M, Takagi H, Shen ZX. Missing quasiparticles and the chemical potential puzzle in the doping evolution of the cuprate superconductors. Phys Rev Lett 2004; 93:267002. [PMID: 15698008 DOI: 10.1103/physrevlett.93.267002] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Indexed: 05/24/2023]
Abstract
The evolution of Ca2-xNaxCuO2Cl2 from Mott insulator to superconductor was studied using angle-resolved photoemission spectroscopy. By measuring both the excitations near the Fermi energy as well as nonbonding states, we tracked the doping dependence of the electronic structure and the chemical potential with unprecedented precision. Our work reveals failures in the standard weakly interacting quasiparticle scenario, including the broad line shapes of the insulator and the apparently paradoxical shift of the chemical potential within the Mott gap. To resolve this, we develop a model where the quasiparticle is vanishingly small at half filling and grows upon doping, allowing us to unify properties such as the dispersion and Fermi wave vector with the chemical potential.
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Affiliation(s)
- K M Shen
- Department of Applied Physics, Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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28
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Zhou XJ, Yoshida T, Lanzara A, Bogdanov PV, Kellar SA, Shen KM, Yang WL, Ronning F, Sasagawa T, Kakeshita T, Noda T, Eisaki H, Uchida S, Lin CT, Zhou F, Xiong JW, Ti WX, Zhao ZX, Fujimori A, Hussain Z, Shen ZX. High-temperature superconductors: Universal nodal Fermi velocity. Nature 2003; 423:398. [PMID: 12761537 DOI: 10.1038/423398a] [Citation(s) in RCA: 276] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- X J Zhou
- Department of Physics, Applied Physics and SSRL, Stanford University, Stanford, California 94305, USA.
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29
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Armitage NP, Ronning F, Lu DH, Kim C, Damascelli A, Shen KM, Feng DL, Eisaki H, Shen ZX, Mang PK, Kaneko N, Greven M, Onose Y, Taguchi Y, Tokura Y. Doping dependence of an n-type cuprate superconductor investigated by angle-resolved photoemission spectroscopy. Phys Rev Lett 2002; 88:257001. [PMID: 12097118 DOI: 10.1103/physrevlett.88.257001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2001] [Indexed: 05/23/2023]
Abstract
We present an angle-resolved photoemission doping dependence study of the n-type cuprate superconductor Nd(2-x)Ce(x)CuO(4+/-delta), from the half-filled Mott insulator to the T(c) = 24 K superconductor. In Nd2CuO4, we reveal the charge-transfer band for the first time. As electrons are doped into the system, this feature's intensity decreases with the concomitant formation of near- E(F) spectral weight. At low doping, the Fermi surface is an electron-pocket (with volume approximately x) centered at (pi,0). Further doping leads to the creation of a new holelike Fermi surface (volume approximately 1+x) centered at (pi,pi). These findings shed light on the Mott gap, its doping evolution, as well as the anomalous transport properties of the n-type cuprates.
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Affiliation(s)
- N P Armitage
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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30
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Uchiyama H, Shen KM, Lee S, Damascelli A, Lu DH, Feng DL, Shen ZX, Tajima S. Electronic structure of MgB2 from angle-resolved photoemission spectroscopy. Phys Rev Lett 2002; 88:157002. [PMID: 11955214 DOI: 10.1103/physrevlett.88.157002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2001] [Indexed: 05/23/2023]
Abstract
The first angle-resolved photoemission spectroscopy results from MgB2 single crystals are reported. Along the GammaK and GammaM directions, we observed three distinct dispersive features approaching the Fermi energy. These can be assigned to the theoretically predicted sigma (B 2p(x,y)) and pi (B 2p(z)) bands. In addition, a small parabolic-like band is detected around the Gamma point, which can be attributed to a surface-derived state. The overall agreement between our results and the band calculations suggests that the electronic structure of MgB2 is of a conventional nature, thus implying that electron correlations are weak and may be of little importance to superconductivity in this system.
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Affiliation(s)
- H Uchiyama
- Superconductivity Research Laboratory, International Superconductivity Technology Center, 1-10-13 Shinonome, Koto-ku, Tokyo 135-0062, Japan
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31
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Feng DL, Damascelli A, Shen KM, Motoyama N, Lu DH, Eisaki H, Shimizu K, Shimoyama Ji JI, Kishio K, Kaneko N, Greven M, Gu GD, Zhou XJ, Kim C, Ronning F, Armitage NP, Shen ZX. Electronic structure of the trilayer cuprate superconductor Bi(2)Sr(2)Ca(2)Cu(3)O(10+delta). Phys Rev Lett 2002; 88:107001. [PMID: 11909381 DOI: 10.1103/physrevlett.88.107001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2001] [Indexed: 05/23/2023]
Abstract
The low-energy electronic structure of the nearly optimally doped trilayer cuprate superconductor Bi(2)Sr(2)Ca(2)Cu(3)O(10+delta) is investigated by angle-resolved photoemission spectroscopy. The normal state quasiparticle dispersion and Fermi surface and the superconducting d-wave gap and coherence peak are observed and compared with those of single- and bilayer systems. We find that both the superconducting gap magnitude and the relative coherence-peak intensity scale linearly with T(c) for various optimally doped materials.
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Affiliation(s)
- D L Feng
- Department of Physics, Applied Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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32
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Armitage NP, Lu DH, Kim C, Damascelli A, Shen KM, Ronning F, Feng DL, Bogdanov P, Shen ZX, Onose Y, Taguchi Y, Tokura Y, Mang PK, Kaneko N, Greven M. Anomalous electronic structure and pseudogap effects in Nd1.85Ce0.15CuO4. Phys Rev Lett 2001; 87:147003. [PMID: 11580672 DOI: 10.1103/physrevlett.87.147003] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2000] [Revised: 05/07/2001] [Indexed: 05/23/2023]
Abstract
We report a high-resolution angle-resolved photoemission spectroscopic study of the electron-doped ( n-type) cuprate superconductor Nd1.85Ce0.15CuO4. We observe regions along the Fermi surface where the near- E(F) intensity is suppressed and the spectral features are broad in a manner reminiscent of the high-energy "pseudogap" in the underdoped p-type (hole doped) cuprates. However, instead of occurring near the (pi,0) region, as in the p-type materials, this pseudogap falls near the intersection of the underlying Fermi surface with the antiferromagnetic Brillouin zone boundary.
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Affiliation(s)
- N P Armitage
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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33
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Feng DL, Armitage NP, Lu DH, Damascelli A, Hu JP, Bogdanov P, Lanzara A, Ronning F, Shen KM, Eisaki H, Kim C, Shen ZX, Shimoyama J, Kishio K. Bilayer splitting in the electronic structure of heavily overdoped Bi(2)Sr(2)CaCu(2)O(8+delta). Phys Rev Lett 2001; 86:5550-5553. [PMID: 11415298 DOI: 10.1103/physrevlett.86.5550] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2001] [Indexed: 05/23/2023]
Abstract
The electronic structure of heavily overdoped Bi(2)Sr(2)CaCu(2)O(8+delta) is investigated by angle-resolved photoemission spectroscopy. The long-sought bilayer band splitting in this two-plane system is observed in both normal and superconducting states, which qualitatively agrees with the bilayer Hubbard model calculations. The maximum bilayer energy splitting is about 88 meV for the normal state feature, while it is only about 20 meV for the superconducting peak.
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Affiliation(s)
- D L Feng
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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34
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Lu DH, Feng DL, Armitage NP, Shen KM, Damascelli A, Kim C, Ronning F, Shen ZX, Bonn DA, Liang R, Hardy WN, Rykov AI, Tajima S. Superconducting gap and strong in-plane anisotropy in untwinned YBa2Cu3O(7-delta). Phys Rev Lett 2001; 86:4370-4373. [PMID: 11328177 DOI: 10.1103/physrevlett.86.4370] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2001] [Indexed: 05/23/2023]
Abstract
With significantly improved sample quality and instrumental resolution, we clearly identify in the ( pi,0) photoemission spectra from YBa(2)Cu(3)O(6.993), in the superconducting state, the long-sought "peak-dip-hump" structure. This advance allows us to investigate the large a-b anisotropy of the in-plane electronic structure including, in particular, a 50% difference in the magnitude of the superconducting gap that scales with the energy position of the hump feature. This anisotropy, likely induced by the presence of the CuO chains, raises serious questions about attempts to quantitatively explain the YBa(2)Cu(3)O(7-delta) data from various experiments using models based on a perfectly square lattice.
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Affiliation(s)
- D H Lu
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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35
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Armitage NP, Lu DH, Feng DL, Kim C, Damascelli A, Shen KM, Ronning F, Shen ZX, Onose Y, Taguchi Y, Tokura Y. Superconducting gap anisotropy in Nd1.85Ce0.15CuO4: results from photoemission. Phys Rev Lett 2001; 86:1126-1129. [PMID: 11178026 DOI: 10.1103/physrevlett.86.1126] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2000] [Indexed: 05/23/2023]
Abstract
We have performed angle resolved photoelectron spectroscopy on the electron doped cuprate superconductor Nd1.85Ce0.15CuO4. A comparison of the leading edge midpoints between the superconducting and normal states reveals a small, but finite shift of 1.5-2 meV near the ( pi,0) position, but no observable shift along the zone diagonal near ( pi/2, pi/2). This is interpreted as evidence for an anisotropic superconducting gap in the electron doped materials, which is consistent with the presence of d-wave superconducting order in this cuprate superconductor.
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Affiliation(s)
- N P Armitage
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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36
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Damascelli A, Lu DH, Shen KM, Armitage NP, Ronning F, Feng DL, Kim C, Shen ZX, Kimura T, Tokura Y, Mao ZQ, Maeno Y. Fermi surface, surface states, and surface reconstruction in Sr2RuO4. Phys Rev Lett 2000; 85:5194-5197. [PMID: 11102219 DOI: 10.1103/physrevlett.85.5194] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2000] [Indexed: 05/23/2023]
Abstract
The electronic structure of Sr2RuO4 is investigated by high angular resolution ARPES at several incident photon energies. We address the controversial issues of the Fermi surface (FS) topology and the van Hove singularity at the M point, showing that a surface state and the replica of the primary FS due to sqrt[2]xsqrt[2] surface reconstruction are responsible for previous conflicting interpretations. The FS thus determined by ARPES is consistent with the de Haas-van Alphen results, and it provides additional information on the detailed shape of the alpha, beta, and gamma sheets.
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Affiliation(s)
- A Damascelli
- Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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37
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Feng DL, Lu DH, Shen KM, Kim C, Eisaki H, Damascelli A, Yoshizaki R, Shimoyama J, Kishio K, Gu GD, Oh S, Andrus A, O'Donnell J, Eckstein JN, Shen Z. Signature of superfluid density in the single-particle excitation spectrum of Bi(2)Sr(2)CaCu(2)O(8+delta). Science 2000; 289:277-81. [PMID: 10894771 DOI: 10.1126/science.289.5477.277] [Citation(s) in RCA: 224] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We report that the doping and temperature dependence of photoemission spectra near the Brillouin zone boundary of Bi(2)Sr(2)CaCu(2)O(8+delta)exhibit unexpected sensitivity to the superfluid density. In the superconducting state, the photoemission peak intensity as a function of doping scales with the superfluid density and the condensation energy. As a function of temperature, the peak intensity shows an abrupt behavior near the superconducting phase transition temperature where phase coherence sets in, rather than near the temperature where the gap opens. This anomalous manifestation of collective effects in single-particle spectroscopy raises important questions concerning the mechanism of high-temperature superconductivity.
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Affiliation(s)
- DL Feng
- Department of Physics, Applied Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, CA 94305, USA. Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305, Japan. Department of Applied Chem
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