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Zhang D, Chen KW, Zheng G, Yu F, Shi M, Zhu Y, Chan A, Jenkins K, Ying J, Xiang Z, Chen X, Li L. Large oscillatory thermal hall effect in kagome metals. Nat Commun 2024; 15:6224. [PMID: 39043657 PMCID: PMC11266402 DOI: 10.1038/s41467-024-50336-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 07/04/2024] [Indexed: 07/25/2024] Open
Abstract
The thermal Hall effect recently provided intriguing probes to the ground state of exotic quantum matters. These observations of transverse thermal Hall signals lead to the debate on the fermionic versus bosonic origins of these phenomena. The recent report of quantum oscillations (QOs) in Kitaev spin liquid points to a possible resolution. The Landau level quantization would most likely capture only the fermionic thermal transport effect. However, the QOs in the thermal Hall effect are generally hard to detect. In this work, we report the observation of a large oscillatory thermal Hall effect of correlated Kagome metals. We detect a 180-degree phase change of the oscillation and demonstrate the phase flip as an essential feature for QOs in the thermal transport properties. More importantly, the QOs in the thermal Hall channel are more profound than those in the electrical Hall channel, which strongly violates the Wiedemann-Franz (WF) law for QOs. This result presents the oscillatory thermal Hall effect as a powerful probe to the correlated quantum materials.
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Affiliation(s)
- Dechen Zhang
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Kuan-Wen Chen
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Guoxin Zheng
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Fanghang Yu
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, China
| | - Mengzhu Shi
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, China
| | - Yuan Zhu
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Aaron Chan
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Kaila Jenkins
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - Jianjun Ying
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, China
| | - Ziji Xiang
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, China
| | - Xianhui Chen
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, China
| | - Lu Li
- Department of Physics, University of Michigan, Ann Arbor, MI, USA.
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2
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Šilhavík M, Kumar P, Levinský P, Zafar ZA, Hejtmánek J, Červenka J. Anderson Localization of Phonons in Thermally Superinsulating Graphene Aerogels with Metal-Like Electrical Conductivity. SMALL METHODS 2024:e2301536. [PMID: 38577909 DOI: 10.1002/smtd.202301536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 03/24/2024] [Indexed: 04/06/2024]
Abstract
In the quest to improve energy efficiency and design better thermal insulators, various engineering strategies have been extensively investigated to minimize heat transfer through a material. Yet, the suppression of thermal transport in a material remains elusive because heat can be transferred by multiple energy carriers. Here, the realization of Anderson localization of phonons in a random 3D elastic network of graphene is reported. It is shown that thermal conductivity in a cellular graphene aerogel can be drastically reduced to 0.9 mW m-1 K-1 by the application of compressive strain while keeping a high metal-like electrical conductivity of 120 S m-1 and ampacity of 0.9 A. The experiments reveal that the strain can cause phonon localization over a broad compression range. The remaining heat flow in the material is dominated by charge transport. Conversely, electrical conductivity exhibits a gradual increase with increasing compressive strain, opposite to the thermal conductivity. These results imply that strain engineering provides the ability to independently tune charge and heat transport, establishing a new paradigm for controlling phonon and charge conduction in solids. This approach will enable the development of a new type of high-performance insulation solutions and thermally superinsulating materials with metal-like electrical conductivity.
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Affiliation(s)
- Martin Šilhavík
- Department of Thin Films and Nanostructures, FZU - Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, Prague, 162 00, Czech Republic
| | - Prabhat Kumar
- Department of Thin Films and Nanostructures, FZU - Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, Prague, 162 00, Czech Republic
| | - Petr Levinský
- Department of Magnetics and Superconductors, FZU - Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, Prague, 162 00, Czech Republic
| | - Zahid Ali Zafar
- Department of Thin Films and Nanostructures, FZU - Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, Prague, 162 00, Czech Republic
| | - Jiří Hejtmánek
- Department of Magnetics and Superconductors, FZU - Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, Prague, 162 00, Czech Republic
| | - Jiří Červenka
- Department of Thin Films and Nanostructures, FZU - Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, Prague, 162 00, Czech Republic
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3
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Torres F, Basaran AC, Schuller IK. Thermal Management in Neuromorphic Materials, Devices, and Networks. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2205098. [PMID: 36067752 DOI: 10.1002/adma.202205098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 08/30/2022] [Indexed: 06/15/2023]
Abstract
Machine learning has experienced unprecedented growth in recent years, often referred to as an "artificial intelligence revolution." Biological systems inspire the fundamental approach for this new computing paradigm: using neural networks to classify large amounts of data into sorting categories. Current machine-learning schemes implement simulated neurons and synapses on standard computers based on a von Neumann architecture. This approach is inefficient in energy consumption, and thermal management, motivating the search for hardware-based systems that imitate the brain. Here, the present state of thermal management of neuromorphic computing technology and the challenges and opportunities of the energy-efficient implementation of neuromorphic devices are considered. The main features of brain-inspired computing and quantum materials for implementing neuromorphic devices are briefly described, the brain criticality and resistive switching-based neuromorphic devices are discussed, the energy and electrical considerations for spiking-based computation are presented, the fundamental features of the brain's thermal regulation are addressed, the physical mechanisms for thermal management and thermoelectric control of materials and neuromorphic devices are analyzed, and challenges and new avenues for implementing energy-efficient computing are described.
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Affiliation(s)
- Felipe Torres
- Physics Department, Faculty of Science, University of Chile, 653, Santiago, 7800024, Chile
- Center of Nanoscience and Nanotechnology (CEDENNA), Av. Ecuador 3493, Santiago, 9170124, Chile
| | - Ali C Basaran
- Department of Physics and Center for Advanced Nanoscience, University of California San Diego, La Jolla, CA, 92093, USA
| | - Ivan K Schuller
- Department of Physics and Center for Advanced Nanoscience, University of California San Diego, La Jolla, CA, 92093, USA
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4
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Superconductor-insulator transition in space charge doped one unit cell Bi 2.1Sr 1.9CaCu 2O 8+x. Nat Commun 2021; 12:2926. [PMID: 34006876 PMCID: PMC8131387 DOI: 10.1038/s41467-021-23183-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 04/16/2021] [Indexed: 11/08/2022] Open
Abstract
The superconductor-insulator transition in two dimensions is a prototype continuous quantum phase transition at absolute zero, driven by a parameter other than temperature. Here we reveal this transition in one unit-cell Bi2.1Sr1.9CaCu2O8+x by space charge doping, a field effect electrostatic doping technique. We determine the related critical parameters and develop a reliable way to estimate doping in the nonsuperconducting region, a crucial and central problem in these materials. Finite-size scaling analysis yields a critical doping of 0.057 holes/Cu, a critical resistance of ~6.85 kΩ and a scaling exponent product νz ~ 1.57. These results, together with earlier work in other materials, provide a coherent picture of the superconductor-insulator transition and its bosonic nature in the underdoped regime of emerging superconductivity in high critical temperature superconductors. Previous work on critical scaling at the superconductor-to-insulator transition has shown variations across different materials. Here, the authors use a space charge doping technique to tune the transition in a single layer cuprate sample and present evidence of the universal scaling behaviour.
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5
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Li N, Huang Q, Yue XY, Chu WJ, Chen Q, Choi ES, Zhao X, Zhou HD, Sun XF. Possible itinerant excitations and quantum spin state transitions in the effective spin-1/2 triangular-lattice antiferromagnet Na 2BaCo(PO 4) 2. Nat Commun 2020; 11:4216. [PMID: 32839456 PMCID: PMC7445251 DOI: 10.1038/s41467-020-18041-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 08/03/2020] [Indexed: 11/09/2022] Open
Abstract
The most fascinating feature of certain two-dimensional (2D) gapless quantum spin liquid (QSL) is that their spinon excitations behave like the fermionic carriers of a paramagnetic metal. The spinon Fermi surface is then expected to produce a linear increase of the thermal conductivity with temperature that should manifest via a residual value (κ0/T) in the zero-temperature limit. However, this linear in T behavior has been reported for very few QSL candidates. Here, we studied the ultralow-temperature thermal conductivity of an effective spin-1/2 triangular QSL candidate Na2BaCo(PO4)2, which has an antiferromagnetic order at very low temperature (TN ~ 148 mK), and observed a finite κ0/T extrapolated from the data above TN. Moreover, while approaching zero temperature, it exhibits series of quantum spin state transitions with applied field along the c axis. These observations indicate that Na2BaCo(PO4)2 possibly behaves as a gapless QSL with itinerant spin excitations above TN and its strong quantum spin fluctuations persist below TN.
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Affiliation(s)
- N Li
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China
| | - Q Huang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996-1200, USA
| | - X Y Yue
- Institute of Physical Science and Information Technology, Anhui University, 230601, Hefei, Anhui, People's Republic of China
| | - W J Chu
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China
| | - Q Chen
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996-1200, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310-3706, USA
| | - X Zhao
- School of Physical Sciences, University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996-1200, USA.
| | - X F Sun
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China. .,Institute of Physical Science and Information Technology, Anhui University, 230601, Hefei, Anhui, People's Republic of China.
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6
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Zhou X, Peets DC, Morgan B, Huttema WA, Murphy NC, Thewalt E, Truncik CJS, Turner PJ, Koenig AJ, Waldram JR, Hosseini A, Liang R, Bonn DA, Hardy WN, Broun DM. Logarithmic Upturn in Low-Temperature Electronic Transport as a Signature of d-Wave Order in Cuprate Superconductors. PHYSICAL REVIEW LETTERS 2018; 121:267004. [PMID: 30636125 DOI: 10.1103/physrevlett.121.267004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 09/13/2018] [Indexed: 06/09/2023]
Abstract
In cuprate superconductors, high magnetic fields have been used extensively to suppress superconductivity and expose the underlying normal state. Early measurements revealed insulatinglike behavior in underdoped material versus temperature T, in which resistivity increases on cooling with a puzzling log(1/T) form. We instead use microwave measurements of flux-flow resistivity in YBa_{2}Cu_{3}O_{6+y} and Tl_{2}Ba_{2}CuO_{6+δ} to study charge transport deep inside the superconducting phase, in the low-temperature and low-field regime. Here, the transition from metallic low-temperature resistivity (dρ/dT>0) to a log(1/T) upturn persists throughout the superconducting doping range, including a regime at high carrier dopings in which the field-revealed normal-state resistivity is Fermi-liquid-like. The log(1/T) form is thus likely a signature of d-wave superconducting order, and the field-revealed normal state's log(1/T) resistivity may indicate the free-flux-flow regime of a phase-disordered d-wave superconductor.
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Affiliation(s)
- Xiaoqing Zhou
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
- Department of Physics, University of Colorado, Boulder, Colorado 80309-0390, USA
| | - D C Peets
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- State Key Laboratory of Surface Physics, Department of Physics, and Advanced Materials Laboratory, Fudan University, Shanghai 200438, People's Republic of China
| | - Benjamin Morgan
- Cavendish Laboratory, Madingley Road, Cambridge CB3 0HE, United Kingdom
| | - W A Huttema
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - N C Murphy
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - E Thewalt
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - C J S Truncik
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - P J Turner
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - A J Koenig
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - J R Waldram
- Cavendish Laboratory, Madingley Road, Cambridge CB3 0HE, United Kingdom
| | - A Hosseini
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Ruixing Liang
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario MG5 1Z8, Canada
| | - D A Bonn
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario MG5 1Z8, Canada
| | - W N Hardy
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario MG5 1Z8, Canada
| | - D M Broun
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
- Canadian Institute for Advanced Research, Toronto, Ontario MG5 1Z8, Canada
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7
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Lee S, Hippalgaonkar K, Yang F, Hong J, Ko C, Suh J, Liu K, Wang K, Urban JJ, Zhang X, Dames C, Hartnoll SA, Delaire O, Wu J. Anomalously low electronic thermal conductivity in metallic vanadium dioxide. Science 2017; 355:371-374. [DOI: 10.1126/science.aag0410] [Citation(s) in RCA: 230] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 12/22/2016] [Indexed: 01/18/2023]
Affiliation(s)
- Sangwook Lee
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
- School of Materials Science and Engineering, Kyungpook National University, Daegu 41566, South Korea
| | - Kedar Hippalgaonkar
- Department of Mechanical Engineering, University of California, Berkeley, CA 94720, USA
- Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, Innovis, 08-03, 138634 Singapore
| | - Fan Yang
- Department of Mechanical Engineering, University of California, Berkeley, CA 94720, USA
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jiawang Hong
- School of Aerospace Engineering and Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Changhyun Ko
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
| | - Joonki Suh
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
| | - Kai Liu
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, LBNL, Berkeley, CA 94720, USA
| | - Kevin Wang
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
| | - Jeffrey J. Urban
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Xiang Zhang
- Department of Mechanical Engineering, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, LBNL, Berkeley, CA 94720, USA
- Department of Physics, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Chris Dames
- Department of Mechanical Engineering, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, LBNL, Berkeley, CA 94720, USA
| | - Sean A. Hartnoll
- Department of Physics, Stanford University, Stanford, CA 94305, USA
| | - Olivier Delaire
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Junqiao Wu
- Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, LBNL, Berkeley, CA 94720, USA
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8
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Li Y, Tabis W, Yu G, Barišić N, Greven M. Hidden Fermi-liquid Charge Transport in the Antiferromagnetic Phase of the Electron-Doped Cuprate Superconductors. PHYSICAL REVIEW LETTERS 2016; 117:197001. [PMID: 27858438 DOI: 10.1103/physrevlett.117.197001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Indexed: 06/06/2023]
Abstract
Systematic analysis of the planar resistivity, Hall effect, and cotangent of the Hall angle for the electron-doped cuprates reveals underlying Fermi-liquid behavior even deep in the antiferromagnetic part of the phase diagram. The transport scattering rate exhibits a quadratic temperature dependence, and is nearly independent of doping and compound and carrier type (electrons versus holes), and hence is universal. Our analysis moreover indicates that the material-specific resistivity upturn at low temperatures and low doping has the same origin in both electron- and hole-doped cuprates.
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Affiliation(s)
- Yangmu Li
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - W Tabis
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
- AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, 30-059 Krakow, Poland
| | - G Yu
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - N Barišić
- Fakultät für Physik, Technische Universität Wien, Wiedner Hauptstraße 8, 1040 Wien, Austria
- Department of Physics, Faculty of Science, University of Zagreb, HR-10000 Zagreb, Croatia
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Leng X, Garcia-Barriocanal J, Bose S, Lee Y, Goldman AM. Electrostatic control of the evolution from a superconducting phase to an insulating phase in ultrathin YBa₂Cu₃O(7-x) films. PHYSICAL REVIEW LETTERS 2011; 107:027001. [PMID: 21797633 DOI: 10.1103/physrevlett.107.027001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Indexed: 05/31/2023]
Abstract
The electrical transport properties of ultrathin YBa₂Cu₃O(7-x) films have been modified using an electric double layer transistor configuration employing an ionic liquid. A clear evolution from superconductor to insulator was observed in nominally 7 unit-cell-thick films. Using a finite size scaling analysis, curves of resistance versus temperature, R(T), over the temperature range from 6 to 22 K were found to collapse onto a single scaling function, which suggests the presence of a quantum critical point. However, the scaling fails at the lowest temperatures indicating the possible presence of an additional phase between the superconducting and insulating regimes.
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Affiliation(s)
- Xiang Leng
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
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10
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Ando Y. Comment on "onset of a boson mode at the superconducting critical point of underdoped YBa2Cu3Oy". PHYSICAL REVIEW LETTERS 2008; 100:029701-029702. [PMID: 18232941 DOI: 10.1103/physrevlett.100.029701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Indexed: 05/25/2023]
Affiliation(s)
- Yoichi Ando
- Institute of Scientific and Industrial Research Osaka University Ibaraki, Osaka 567-0047, Japan
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11
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Affiliation(s)
- A J Millis
- Department of Physics, Columbia University, New York, NY 10027, USA.
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