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Meng K, Li Z, Chen P, Ma X, Huang J, Li J, Qin F, Qiu C, Zhang Y, Zhang D, Deng Y, Yang Y, Gu G, Hwang HY, Xue QK, Cui Y, Yuan H. Superionic fluoride gate dielectrics with low diffusion barrier for two-dimensional electronics. NATURE NANOTECHNOLOGY 2024; 19:932-940. [PMID: 38750167 DOI: 10.1038/s41565-024-01675-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 04/10/2024] [Indexed: 07/04/2024]
Abstract
Exploration of new dielectrics with a large capacitive coupling is an essential topic in modern electronics when conventional dielectrics suffer from the leakage issue near the breakdown limit. Here, to address this looming challenge, we demonstrate that rare-earth metal fluorides with extremely low ion migration barriers can generally exhibit an excellent capacitive coupling over 20 μF cm-2 (with an equivalent oxide thickness of ~0.15 nm and a large effective dielectric constant near 30) and great compatibility with scalable device manufacturing processes. Such a static dielectric capability of superionic fluorides is exemplified by MoS2 transistors exhibiting high on/off current ratios over 108, ultralow subthreshold swing of 65 mV dec-1 and ultralow leakage current density of ~10-6 A cm-2. Therefore, the fluoride-gated logic inverters can achieve notably higher static voltage gain values (surpassing ~167) compared with a conventional dielectric. Furthermore, the application of fluoride gating enables the demonstration of NAND, NOR, AND and OR logic circuits with low static energy consumption. In particular, the superconductor-insulator transition at the clean-limit Bi2Sr2CaCu2O8+δ can also be realized through fluoride gating. Our findings highlight fluoride dielectrics as a pioneering platform for advanced electronic applications and for tailoring emergent electronic states in condensed matter.
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Affiliation(s)
- Kui Meng
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Zeya Li
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Peng Chen
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Xingyue Ma
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Junwei Huang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Jiayi Li
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Feng Qin
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Caiyu Qiu
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Yilin Zhang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Ding Zhang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China
| | - Yu Deng
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
| | - Yurong Yang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
| | - Genda Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - Harold Y Hwang
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Qi-Kun Xue
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China.
- Department of Physics, Southern University of Science and Technology, Shenzhen, China.
| | - Yi Cui
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA.
- Department of Material Science and Engineering, Stanford University, Stanford, CA, USA.
| | - Hongtao Yuan
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
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2
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Hu S, Qiao J, Gu G, Xue QK, Zhang D. Vortex entropy and superconducting fluctuations in ultrathin underdoped Bi 2Sr 2CaCu 2O 8+x superconductor. Nat Commun 2024; 15:4818. [PMID: 38844439 PMCID: PMC11156657 DOI: 10.1038/s41467-024-48899-6] [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: 05/22/2023] [Accepted: 05/15/2024] [Indexed: 06/09/2024] Open
Abstract
Vortices in superconductors can help identify emergent phenomena but certain fundamental aspects of vortices, such as their entropy, remain poorly understood. Here, we study the vortex entropy in underdoped Bi2Sr2CaCu2O8+x by measuring both magneto-resistivity and Nernst effect on ultrathin flakes (≤2 unit-cell). We extract the London penetration depth from the magneto-transport measurements on samples with different doping levels. It reveals that the superfluid phase stiffness ρs scales linearly with the superconducting transition temperature Tc, down to the extremely underdoped case. On the same batch of ultrathin flakes, we measure the Nernst effect via on-chip thermometry. Together, we obtain the vortex entropy and find that it decays exponentially with Tc or ρs. We further analyze the Nernst signal above Tc in the framework of Gaussian superconducting fluctuations. The combination of electrical and thermoelectric measurements in the two-dimensional limit provides fresh insight into high temperature superconductivity.
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Affiliation(s)
- Shuxu Hu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China
| | - Jiabin Qiao
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China.
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement, School of Physics, Beijing Institute of Technology, Beijing, China.
- Beijing Academy of Quantum Information Sciences, Beijing, China.
| | - Genda Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - Qi-Kun Xue
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China.
- Beijing Academy of Quantum Information Sciences, Beijing, China.
- Southern University of Science and Technology, Shenzhen, China.
- Frontier Science Center for Quantum Information, Beijing, China.
| | - Ding Zhang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China.
- Beijing Academy of Quantum Information Sciences, Beijing, China.
- Frontier Science Center for Quantum Information, Beijing, China.
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, Japan.
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3
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Ghosh S, Patil V, Basu A, Kuldeep, Dutta A, Jangade DA, Kulkarni R, Thamizhavel A, Steiner JF, von Oppen F, Deshmukh MM. High-temperature Josephson diode. NATURE MATERIALS 2024; 23:612-618. [PMID: 38321240 DOI: 10.1038/s41563-024-01804-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 01/08/2024] [Indexed: 02/08/2024]
Abstract
Many superconducting systems with broken time-reversal and inversion symmetry show a superconducting diode effect, a non-reciprocal phenomenon analogous to semiconducting p-n-junction diodes. While the superconducting diode effect lays the foundation for realizing ultralow dissipative circuits, Josephson-phenomena-based diode effect (JDE) can enable the realization of protected qubits. The superconducting diode effect and JDE reported thus far are at low temperatures (~4 K), limiting their applications. Here we demonstrate JDE persisting up to 77 K using an artificial Josephson junction of twisted layers of Bi2Sr2CaCu2O8+δ. JDE manifests as an asymmetry in the magnitude and distributions of switching currents, attaining the maximum at 45° twist. The asymmetry is induced by and tunable with a very small magnetic field applied perpendicular to the junction and arises due to interaction between Josephson and Abrikosov vortices. We report a large asymmetry of 60% at 20 K. Our results provide a path towards realizing superconducting Josephson circuits at liquid-nitrogen temperature.
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Affiliation(s)
- Sanat Ghosh
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India.
| | - Vilas Patil
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - Amit Basu
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - Kuldeep
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - Achintya Dutta
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - Digambar A Jangade
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - Ruta Kulkarni
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - A Thamizhavel
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India
| | - Jacob F Steiner
- Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Berlin, Germany
| | - Felix von Oppen
- Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Berlin, Germany
| | - Mandar M Deshmukh
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, India.
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Xiao Y, Wu J, Dadap JI, Awan KM, Yang D, Liang J, Watanabe K, Taniguchi T, Zonno M, Bluschke M, Eisaki H, Greven M, Damascelli A, Ye Z. Optically Probing Unconventional Superconductivity in Atomically Thin Bi 2Sr 2Ca 0.92Y 0.08Cu 2O 8+δ. NANO LETTERS 2024; 24:3986-3993. [PMID: 38501960 DOI: 10.1021/acs.nanolett.4c00559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Atomically thin cuprates exhibiting a superconducting phase transition temperature similar to that of the bulk have recently been realized, although the device fabrication remains a challenge and limits the potential for many novel studies and applications. Here, we use an optical pump-probe approach to noninvasively study the unconventional superconductivity in atomically thin Bi2Sr2Ca0.92Y0.08Cu2O8+δ (Y-Bi2212). Apart from finding an optical response due to the superconducting phase transition that is similar to that of bulk Y-Bi2212, we observe that the sign and amplitude of the pump-probe signal in atomically thin flakes vary significantly in different dielectric environments depending on the nature of the optical excitation. By exploiting the spatial resolution of the optical probe, we uncover the exceptional sensitivity of monolayer Y-Bi2212 to the environment. Our results provide the first optical evidence for the intralayer nature of the superconducting condensate in Bi2212 and highlight the role of double-sided encapsulation in preserving superconductivity in atomically thin cuprates.
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Affiliation(s)
- Yunhuan Xiao
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Jingda Wu
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Jerry I Dadap
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Kashif Masud Awan
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Dongyang Yang
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Jing Liang
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Marta Zonno
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Martin Bluschke
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Hiroshi Eisaki
- Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan
| | - Martin Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Andrea Damascelli
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Ziliang Ye
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
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5
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Zhao SYF, Cui X, Volkov PA, Yoo H, Lee S, Gardener JA, Akey AJ, Engelke R, Ronen Y, Zhong R, Gu G, Plugge S, Tummuru T, Kim M, Franz M, Pixley JH, Poccia N, Kim P. Time-reversal symmetry breaking superconductivity between twisted cuprate superconductors. Science 2023; 382:1422-1427. [PMID: 38060675 DOI: 10.1126/science.abl8371] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 11/07/2023] [Indexed: 12/23/2023]
Abstract
Twisted interfaces between stacked van der Waals (vdW) cuprate crystals present a platform for engineering superconducting order parameters by adjusting stacking angles. Using a cryogenic assembly technique, we construct twisted vdW Josephson junctions (JJs) at atomically sharp interfaces between Bi2Sr2CaCu2O8+x crystals, with quality approaching the limit set by intrinsic JJs. Near 45° twist angle, we observe fractional Shapiro steps and Fraunhofer patterns, consistent with the existence of two degenerate Josephson ground states related by time-reversal symmetry (TRS). By programming the JJ current bias sequence, we controllably break TRS to place the JJ into either of the two ground states, realizing reversible Josephson diodes without external magnetic fields. Our results open a path to engineering topological devices at higher temperatures.
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Affiliation(s)
- S Y Frank Zhao
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Xiaomeng Cui
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Pavel A Volkov
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Center for Materials Theory, Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854, USA
- Department of Physics, University of Connecticut, Storrs, CT 06269, USA
| | - Hyobin Yoo
- Department of Physics, Institute of Emergent Materials, Sogang University, Seoul 04107, Korea
| | - Sangmin Lee
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
| | - Jules A Gardener
- Center for Nanoscale Systems, Harvard University, Cambridge, MA 02138, USA
| | - Austin J Akey
- Center for Nanoscale Systems, Harvard University, Cambridge, MA 02138, USA
| | - Rebecca Engelke
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Yuval Ronen
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Ruidan Zhong
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Genda Gu
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Stephan Plugge
- Department of Physics and Astronomy and Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Tarun Tummuru
- Department of Physics and Astronomy and Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Miyoung Kim
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
| | - Marcel Franz
- Department of Physics and Astronomy and Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jedediah H Pixley
- Center for Materials Theory, Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854, USA
| | - Nicola Poccia
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden), 01069 Dresden, Germany
| | - Philip Kim
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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6
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Li Y, Wan Q, Xu N. Recent Advances in Moiré Superlattice Systems by Angle-Resolved Photoemission Spectroscopy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2305175. [PMID: 37689836 DOI: 10.1002/adma.202305175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/16/2023] [Indexed: 09/11/2023]
Abstract
The last decade has witnessed a flourish in 2D materials including graphene and transition metal dichalcogenides (TMDs) as atomic-scale Legos. Artificial moiré superlattices via stacking 2D materials with a twist angle and/or a lattice mismatch have recently become a fertile playground exhibiting a plethora of emergent properties beyond their building blocks. These rich quantum phenomena stem from their nontrivial electronic structures that are effectively tuned by the moiré periodicity. Modern angle-resolved photoemission spectroscopy (ARPES) can directly visualize electronic structures with decent momentum, energy, and spatial resolution, thus can provide enlightening insights into fundamental physics in moiré superlattice systems and guides for designing novel devices. In this review, first, a brief introduction is given on advanced ARPES techniques and basic ideas of band structures in a moiré superlattice system. Then ARPES research results of various moiré superlattice systems are highlighted, including graphene on substrates with small lattice mismatches, twisted graphene/TMD moiré systems, and high-order moiré superlattice systems. Finally, it discusses important questions that remain open, challenges in current experimental investigations, and presents an outlook on this field of research.
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Affiliation(s)
- Yiwei Li
- Institute for Advanced Studies (IAS), Wuhan University, Wuhan, 430072, China
| | - Qiang Wan
- Institute for Advanced Studies (IAS), Wuhan University, Wuhan, 430072, China
| | - Nan Xu
- Institute for Advanced Studies (IAS), Wuhan University, Wuhan, 430072, China
- Wuhan Institute of Quantum Technology, Wuhan, 430206, China
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7
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Wang H, Zhu Y, Bai Z, Wang Z, Hu S, Xie HY, Hu X, Cui J, Huang M, Chen J, Ding Y, Zhao L, Li X, Zhang Q, Gu L, Zhou XJ, Zhu J, Zhang D, Xue QK. Prominent Josephson tunneling between twisted single copper oxide planes of Bi 2Sr 2-xLa xCuO 6+y. Nat Commun 2023; 14:5201. [PMID: 37626041 PMCID: PMC10457331 DOI: 10.1038/s41467-023-40525-1] [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: 12/04/2022] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
Josephson tunneling in twisted cuprate junctions provides a litmus test for the pairing symmetry, which is fundamental for understanding the microscopic mechanism of high temperature superconductivity. This issue is rekindled by experimental advances in van der Waals stacking and the proposal of an emergent d+id-wave. So far, all experiments have been carried out on Bi2Sr2CaCu2O8+x (Bi-2212) with double CuO2 planes but show controversial results. Here, we investigate junctions made of Bi2Sr2-xLaxCuO6+y (Bi-2201) with single CuO2 planes. Our on-site cold stacking technique ensures uncompromised crystalline quality and stoichiometry at the interface. Junctions with carefully calibrated twist angles around 45° show strong Josephson tunneling and conventional temperature dependence. Furthermore, we observe standard Fraunhofer diffraction patterns and integer Fiske steps in a junction with a twist angle of 45.0±0.2°. Together, these results pose strong constraints on the d or d+id-wave pairing and suggest an indispensable isotropic pairing component.
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Affiliation(s)
- Heng Wang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Yuying Zhu
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China.
- Hefei National Laboratory, Hefei, 230088, China.
| | - Zhonghua Bai
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Zechao Wang
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, 100084, China
- Ji Hua Laboratory, Foshan, Guangdong, 528200, China
| | - Shuxu Hu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Hong-Yi Xie
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Xiaopeng Hu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Jian Cui
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Miaoling Huang
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Jianhao Chen
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100091, China
| | - Ying Ding
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Lin Zhao
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Xinyan Li
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Qinghua Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Lin Gu
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, 100084, China
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - X J Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jing Zhu
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, 100084, China
- Ji Hua Laboratory, Foshan, Guangdong, 528200, China
| | - Ding Zhang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China.
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China.
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan.
| | - Qi-Kun Xue
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, 100084, China.
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China.
- Southern University of Science and Technology, Shenzhen, 518055, China.
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8
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Guo Y, Qiu D, Shao M, Song J, Wang Y, Xu M, Yang C, Li P, Liu H, Xiong J. Modulations in Superconductors: Probes of Underlying Physics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209457. [PMID: 36504310 DOI: 10.1002/adma.202209457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/16/2022] [Indexed: 06/02/2023]
Abstract
The importance of modulations is elevated to an unprecedented level, due to the delicate conditions required to bring out exotic phenomena in quantum materials, such as topological materials, magnetic materials, and superconductors. Recently, state-of-the-art modulation techniques in material science, such as electric-double-layer transistor, piezoelectric-based strain apparatus, angle twisting, and nanofabrication, have been utilized in superconductors. They not only efficiently increase the tuning capability to the broader ranges but also extend the tuning dimensionality to unprecedented degrees of freedom, including quantum fluctuations of competing phases, electronic correlation, and phase coherence essential to global superconductivity. Here, for a comprehensive review, these techniques together with the established modulation methods, such as elemental substitution, annealing, and polarization-induced gating, are contextualized. Depending on the mechanism of each method, the modulations are categorized into stoichiometric manipulation, electrostatic gating, mechanical modulation, and geometrical design. Their recent advances are highlighted by applications in newly discovered superconductors, e.g., nickelates, Kagome metals, and magic-angle graphene. Overall, the review is to provide systematic modulations in emergent superconductors and serve as the coordinate for future investigations, which can stimulate researchers in superconductivity and other fields to perform various modulations toward a thorough understanding of quantum materials.
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Affiliation(s)
- Yehao Guo
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Dong Qiu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Mingxin Shao
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Jingyan Song
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Yang Wang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Minyi Xu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Chao Yang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Peng Li
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Haiwen Liu
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Jie Xiong
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
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9
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Jois S, Lado JL, Gu G, Li Q, Lee JU. Andreev Reflection and Klein Tunneling in High-Temperature Superconductor-Graphene Junctions. PHYSICAL REVIEW LETTERS 2023; 130:156201. [PMID: 37115873 DOI: 10.1103/physrevlett.130.156201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 03/15/2023] [Indexed: 06/19/2023]
Abstract
Scattering processes in quantum materials emerge as resonances in electronic transport, including confined modes, Andreev states, and Yu-Shiba-Rusinov states. However, in most instances, these resonances are driven by a single scattering mechanism. Here, we show the appearance of resonances due to the combination of two simultaneous scattering mechanisms, one from superconductivity and the other from graphene p-n junctions. These resonances stem from Andreev reflection and Klein tunneling that occur at two different interfaces of a hole-doped region of graphene formed at the boundary with superconducting graphene due to proximity effects from Bi_{2}Sr_{2}Ca_{1}Cu_{2}O_{8+δ}. The resonances persist with gating from p^{+}-p and p-n configurations. The suppression of the oscillation amplitude above the bias energy which is comparable to the induced superconducting gap indicates the contribution from Andreev reflection. Our experimental measurements are supported by quantum transport calculations in such interfaces, leading to analogous resonances. Our results put forward a hybrid scattering mechanism in graphene-high-temperature superconductor heterojunctions of potential impact for graphene-based Josephson junctions.
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Affiliation(s)
- Sharadh Jois
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, New York 12203, USA
| | - Jose L Lado
- Department of Applied Physics, Aalto University, 00076 Aalto, Espoo, Finland
| | - Genda Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Qiang Li
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
| | - Ji Ung Lee
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, New York 12203, USA
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10
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Lei B, Ma D, Liu S, Sun Z, Shi M, Zhuo W, Yu F, Gu G, Wang Z, Chen X. Manipulating high-temperature superconductivity by oxygen doping in Bi 2Sr 2CaCu 2O 8+δ thin flakes. Natl Sci Rev 2022; 9:nwac089. [PMID: 36415315 PMCID: PMC9671661 DOI: 10.1093/nsr/nwac089] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 01/17/2022] [Accepted: 02/15/2022] [Indexed: 09/08/2024] Open
Abstract
Harnessing the fascinating properties of correlated oxides requires precise control of their carrier density. Compared to other methods, oxygen doping provides an effective and more direct way to tune the electronic properties of correlated oxides. Although several approaches, such as thermal annealing and oxygen migration, have been introduced to change the oxygen content, a continuous and reversible solution that can be integrated with modern electronic technology is much in demand. Here, we report a novel ionic field-effect transistor using solid Gd-doped CeO2 as the gate dielectric, which shows a remarkable carrier-density-tuning ability via electric-field-controlled oxygen concentration at room temperature. In Bi2Sr2CaCu2O8+δ (Bi-2212) thin flakes, we achieve a reversible superconductor-insulator transition by driving oxygen ions in and out of the samples with electric fields, and map out the phase diagram all the way from the insulating regime to the over-doped superconducting regime by continuously changing the oxygen doping level. Scaling analysis indicates that the reversible superconductor-insulator transition for the Bi-2212 thin flakes follows the theoretical description of a two-dimensional quantum phase transition. Our work provides a route for realizing electric-field control of phase transition in correlated oxides. Moreover, the configuration of this type of transistor makes heterostructure/interface engineering possible, thus having the potential to serve as the next-generation all-solid-state field-effect transistor.
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Affiliation(s)
- Bin Lei
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
- CASCenter for Excellence in Quantum Information and Quantum Physics, Hefei 230026, China
| | - Donghui Ma
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Shihao Liu
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Zeliang Sun
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Mengzhu Shi
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Weizhuang Zhuo
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Fanghang Yu
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Genda Gu
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973-5000, USA
| | - Zhenyu Wang
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
- CASCenter for Excellence in Quantum Information and Quantum Physics, Hefei 230026, China
| | - Xianhui Chen
- Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei 230026, China
- CASCenter for Excellence in Quantum Information and Quantum Physics, Hefei 230026, China
- CAS Center for Excellence in Superconducting Electronics (CENSE), Shanghai 200050, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
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11
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Ji JY, Bao T, Wang H, Xu Y, Zhang D, Xue QK. Homogeneous Lateral Lithium Intercalation into Transition Metal Dichalcogenides via Ion Backgating. NANO LETTERS 2022; 22:7336-7342. [PMID: 36122383 DOI: 10.1021/acs.nanolett.2c01705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Lithium intercalation has become a versatile tool for realizing emergent quantum phenomena in two-dimensional (2D) materials. However, the insertion of lithium ions may be accompanied by the creation of wrinkles and cracks, which prevents the material from manifesting its intrinsic properties under substantial charge injection. By using the recently developed ion backgating technique, we successfully realize lateral intercalation in 1T-TiSe2 and 2H-NbSe2, which shows substantially improved sample homogeneity. The homogeneity at high lithium doping is not only demonstrated via low-temperature transport measurements but also directly visualized by topographical imaging through in situ atomic force microscopy (AFM). The application of lateral intercalation to a broad spectrum of 2D materials can greatly facilitate the search for exotic quantum phenomena.
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Affiliation(s)
- Jia-Yi Ji
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
| | - Ting Bao
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
| | - Heng Wang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
| | - Yong Xu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Collaborative Innovation Center for Quantum Matter, Beijing 100084, China
| | - Ding Zhang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Collaborative Innovation Center for Quantum Matter, Beijing 100084, China
| | - Qi-Kun Xue
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Collaborative Innovation Center for Quantum Matter, Beijing 100084, China
- Southern University of Science and Technology, Shenzhen 518055, China
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12
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Little-Parks like oscillations in lightly doped cuprate superconductors. Nat Commun 2022; 13:1316. [PMID: 35288555 PMCID: PMC8921203 DOI: 10.1038/s41467-022-28954-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 02/13/2022] [Indexed: 11/08/2022] Open
Abstract
Understanding the rich and competing electronic orders in cuprate superconductors may provide important insight into the mechanism of high-temperature superconductivity. Here, by measuring Bi2Sr2CaCu2O8+x in the extremely underdoped regime, we obtain evidence for a distinct type of ordering, which manifests itself as resistance oscillations at low magnetic fields (≤10 T) and at temperatures around the superconducting transition. By tuning the doping level p continuously, we reveal that these low-field oscillations occur only when p < 0.1. The oscillation amplitude increases with decreasing p but the oscillation period stays almost constant. We show that these low-field oscillations can be well described by assuming a periodic superconducting structure with a mesh size of about 50 nm. Such a charge order, which is distinctly different from the well-established charge density wave and pair density wave, seems to be an unexpected piece of the puzzle on the correlated physics in cuprates. Understanding the rich electronic orders in cuprate superconductors provide insights into the mechanism of high-temperature superconductivity. Here, the authors report a distinct charge order with Little-Parks like resistance oscillations at magnetic fields up to 10 T and around Tc in lightly doped Bi2Sr2CaCu2O8+x.
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13
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Zhang D, Falson J. Ising pairing in atomically thin superconductors. NANOTECHNOLOGY 2021; 32:502003. [PMID: 34479228 DOI: 10.1088/1361-6528/ac238d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
Ising-type pairing in atomically thin superconducting materials has emerged as a novel means of generating devices with resilience to a magnetic field applied parallel to the two-dimensional (2D) plane. In this mini-review, we canvas the state of the field by giving a historical account of 2D superconductors with strongly enhanced in-plane upper critical fields, together with the type-I and type-II Ising pairing mechanisms. We highlight the vital role of spin-orbit coupling in these superconductors and discuss other effects such as symmetry breaking, atomic thicknesses, etc. Finally, we summarize the recent theoretical proposals and highlight the open questions, such as exploring topological superconductivity in these systems and looking for more materials with Ising pairing.
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Affiliation(s)
- Ding Zhang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan
- Beijing Academy of Quantum Information Sciences, Beijing 100193, People's Republic of China
- Frontier Science Center for Quantum Information, Beijing 100084, People's Republic of China
| | - Joseph Falson
- Department of Applied Physics and Materials Science, California Institute of Technology, Pasadena, CA, United States of America
- Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, CA 91125, United States of America
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14
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Coexistence of resistance oscillations and the anomalous metal phase in a lithium intercalated TiSe 2 superconductor. Nat Commun 2021; 12:5342. [PMID: 34504094 PMCID: PMC8429654 DOI: 10.1038/s41467-021-25671-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 08/22/2021] [Indexed: 11/24/2022] Open
Abstract
Superconductivity and charge density wave (CDW) appear in the phase diagram of a variety of materials including the high-Tc cuprate family and many transition metal dichalcogenides (TMDs). Their interplay may give rise to exotic quantum phenomena. Here, we show that superconducting arrays can spontaneously form in TiSe2–a TMD with coexisting superconductivity and CDW—after lithium ion intercalation. We induce a superconducting dome in the phase diagram of LixTiSe2 by using the ionic solid-state gating technique. Around optimal doping, we observe magnetoresistance oscillations, indicating the emergence of periodically arranged domains. In the same temperature, magnetic field and carrier density regime where the resistance oscillations occur, we observe signatures for the anomalous metal—a state with a resistance plateau across a wide temperature range below the superconducting transition. Our study not only sheds further insight into the mechanism for the periodic electronic structure, but also reveals the interplay between the anomalous metal and superconducting fluctuations. The interplay between superconductivity and charge density wave (CDW) gives rise to exotic quantum phenomena. Here, the authors observe magnetoresistance oscillations and an anomalous metal state due to the coexistence of superconductivity and CDW in lithium intercalated TiSe2.
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15
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Indium-contacted van der Waals gap tunneling spectroscopy for van der Waals layered materials. Sci Rep 2021; 11:17790. [PMID: 34493752 PMCID: PMC8423830 DOI: 10.1038/s41598-021-97110-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 08/12/2021] [Indexed: 11/23/2022] Open
Abstract
The electrical phase transition in van der Waals (vdW) layered materials such as transition-metal dichalcogenides and Bi2Sr2CaCu2O8+x (Bi-2212) high-temperature superconductor has been explored using various techniques, including scanning tunneling and photoemission spectroscopies, and measurements of electrical resistance as a function of temperature. In this study, we develop one useful method to elucidate the electrical phases in vdW layered materials: indium (In)-contacted vdW tunneling spectroscopy for 1T-TaS2, Bi-2212 and 2H-MoS2. We utilized the vdW gap formed at an In/vdW material interface as a tunnel barrier for tunneling spectroscopy. For strongly correlated electron systems such as 1T-TaS2 and Bi-2212, pronounced gap features corresponding to the Mott and superconducting gaps were respectively observed at T = 4 K. We observed a gate dependence of the amplitude of the superconducting gap, which has potential applications in a gate-tunable superconducting device with a SiO2/Si substrate. For In/10 nm-thick 2H-MoS2 devices, differential conductance shoulders at bias voltages of approximately ± 0.45 V were observed, which were attributed to the semiconducting gap. These results show that In-contacted vdW gap tunneling spectroscopy in a fashion of field-effect transistor provides feasible and reliable ways to investigate electronic structures of vdW materials.
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16
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Liu G, Bao X, Dong W, Wei Q, Mu H, Zhu W, Wang B, Li J, Shabbir B, Huang Y, Xing G, Yu J, Gao P, Shao H, Li X, Bao Q. Two-Dimensional Bi 2Sr 2CaCu 2O 8+δ Nanosheets for Ultrafast Photonics and Optoelectronics. ACS NANO 2021; 15:8919-8929. [PMID: 33969996 DOI: 10.1021/acsnano.1c01567] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two-dimensional (2D) Bi2Sr2CaCu2O8+δ (BSCCO) is a emerming class of 2D materials with high-temperature superconductivity for which their electronic transport properties have been intensively studied. However, the optical properties, especially nonlinear optical response and the photonic and optoelectronic applications of normal state 2D Bi2Sr2CaCu2O8+δ (Bi-2212), have been largely unexplored. Here, the linear and nonlinear optical properties of mechanically exfoliated Bi-2212 thin flakes are systematically investigated. 2D Bi-2212 shows a profound plasmon absorption in near-infrared wavelength range with ultrafast carrier dynamics as well as tunable nonlinear absorption depending on the thickness. We demonstrated that 2D Bi-2212 can be applied not only as an effective mode-locker for ultrashort pulse generation but also as an active medium for infrared light detection due to its plasmon absorption. Our results may trigger follow up studies on the optical properties of 2D BSCCO and demonstrate potential opportunities for photonic and optoelectronic applications.
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Affiliation(s)
- Guanyu Liu
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
| | - Xiaozhi Bao
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, China
| | - Weikang Dong
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Qi Wei
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, China
| | - Haoran Mu
- Department of Materials Science and Engineering, and ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, Victoria 3800, Australia
| | - Wenguo Zhu
- Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institutes, Jinan University, Guangzhou 510632, China
| | - Bingzhe Wang
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, China
| | - Jianding Li
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, China
| | - Babar Shabbir
- Department of Materials Science and Engineering, and ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, Victoria 3800, Australia
| | - Yuan Huang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Guichuan Xing
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, China
| | - Jianhui Yu
- Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institutes, Jinan University, Guangzhou 510632, China
| | - Peng Gao
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Huaiyu Shao
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, China
| | - Xiangping Li
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
| | - Qiaoliang Bao
- Department of Materials Science and Engineering, and ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, Victoria 3800, Australia
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17
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Qiu D, Gong C, Wang S, Zhang M, Yang C, Wang X, Xiong J. Recent Advances in 2D Superconductors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2006124. [PMID: 33768653 DOI: 10.1002/adma.202006124] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/22/2020] [Indexed: 06/12/2023]
Abstract
The emergence of superconductivity in 2D materials has attracted much attention and there has been rapid development in recent years because of their fruitful physical properties, such as high transition temperature (Tc ), continuous phase transition, and enhanced parallel critical magnetic field (Bc ). Tremendous efforts have been devoted to exploring different physical parameters to figure out the mechanisms behind the unexpected superconductivity phenomena, including adjusting the thickness of samples, fabricating various heterostructures, tuning the carrier density by electric field and chemical doping, and so on. Here, different types of 2D superconductivity with their unique characteristics are introduced, including the conventional Bardeen-Cooper-Schrieffer superconductivity in ultrathin films, high-Tc superconductivity in Fe-based and Cu-based 2D superconductors, unconventional superconductivity in newly discovered twist-angle bilayer graphene, superconductivity with enhanced Bc , and topological superconductivity. A perspective toward this field is then proposed based on academic knowledge from the recently reported literature. The aim is to provide researchers with a clear and comprehensive understanding about the newly developed 2D superconductivity and promote the development of this field much further.
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Affiliation(s)
- Dong Qiu
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Chuanhui Gong
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - SiShuang Wang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Miao Zhang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Chao Yang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Xianfu Wang
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Jie Xiong
- State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China
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18
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Li Z, Sang L, Liu P, Yue Z, Fuhrer MS, Xue Q, Wang X. Atomically Thin Superconductors. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e1904788. [PMID: 32363776 DOI: 10.1002/smll.201904788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 12/18/2019] [Accepted: 03/04/2020] [Indexed: 06/11/2023]
Abstract
In recent years, atomically thin superconductors, including atomically thin elemental superconductors, single layer FeSe films, and few-layer cuprate superconductors, have been studied extensively. This hot research field is mainly driven by the discovery of significant superconductivity enhancement and high-temperature interface superconductivity in single-layer FeSe films epitaxially grown on SrTiO3 substrates in 2012. This study has attracted tremendous research interest and generated more studies focusing on further enhancing superconductivity and finding the origin of the superconductivity. A few years later, research on atomically thin superconductors has extended to cuprate superconductors, unveiling many intriguing properties that have neither been proposed or observed previously. These new discoveries challenge the current theory regarding the superconducting mechanism of unconventional superconductors and indicate new directions on how to achieve high-transition-temperature superconductors. Herein, this exciting recent progress is briefly discussed, with a focus on the recent progress in identifying new atomically thin superconductors.
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Affiliation(s)
- Zhi Li
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), University of Wollongong, Wollongong, NSW, 2525, Australia
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW, 2525, Australia
| | - Lina Sang
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), University of Wollongong, Wollongong, NSW, 2525, Australia
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW, 2525, Australia
| | - Peng Liu
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), University of Wollongong, Wollongong, NSW, 2525, Australia
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW, 2525, Australia
| | - Zengji Yue
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), University of Wollongong, Wollongong, NSW, 2525, Australia
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW, 2525, Australia
| | - Michael S Fuhrer
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), Monash University, Victoria, 3800, Australia
| | - Qikun Xue
- Collaborative Innovation Center of Quantum Matter, Beijing, 100871, China
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Xiaolin Wang
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), University of Wollongong, Wollongong, NSW, 2525, Australia
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW, 2525, Australia
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19
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Ghosh S, Vaidya J, Datta S, Pandeya RP, Jangade DA, Kulkarni RN, Maiti K, Thamizhavel A, Deshmukh MM. On-Demand Local Modification of High-T c Superconductivity in Few Unit-Cell Thick Bi 2 Sr 2 CaCu 2 O 8+δ. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2002220. [PMID: 32743859 DOI: 10.1002/adma.202002220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/03/2020] [Accepted: 07/03/2020] [Indexed: 06/11/2023]
Abstract
High-temperature superconductors (HTSs) are important for potential applications and for understanding the origin of strong correlations. Bi2 Sr2 CaCu2 O8+δ (BSCCO), a van der Waals material, offers a platform to probe the physics down to a unit-cell. Guiding the flow of electrons by patterning 2DEGS and oxide heterostructures has brought new functionality and access to new science. Similarly, modifying superconductivity in HTS locally, on a small length scale, is of immense interest for superconducting electronics. A route to modify superconductivity locally by depositing metal on the surface is reported here by transport studies on few unit-cell thick BSCCO. Deposition of chromium (Cr) on the surface over a selected area of BSCCO results in insulating behavior of the underlying region. Cr locally depletes oxygen in CuO2 planes and disrupts the superconductivity in the layers below. This technique of modifying superconductivity is suitable for making sub-micrometer superconducting wires and more complex superconducting devices.
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Affiliation(s)
- Sanat Ghosh
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Jaykumar Vaidya
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Sawani Datta
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Ram Prakash Pandeya
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Digambar A Jangade
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Ruta N Kulkarni
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Kalobaran Maiti
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Arumugam Thamizhavel
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
| | - Mandar M Deshmukh
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005, India
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20
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Varma Sangani LD, Surya Kanthi RS, Chandra Adak P, Sinha S, Marchawala AH, Taniguchi T, Watanabe K, Deshmukh MM. Facile deterministic cutting of 2D materials for twistronics using a tapered fibre scalpel. NANOTECHNOLOGY 2020; 31:32LT02. [PMID: 32316001 DOI: 10.1088/1361-6528/ab8b93] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We present a quick and reliable method to cut 2D materials for creating 2D twisted heterostructures and devices. We demonstrate the effectiveness of using a tapered fibre scalpel for cutting graphene. Electrical transport measurements show evidence of the desired twist between the graphene layers fabricated using our technique. Statistics of the number of successfully twisted stacks made using our method is compared with h-BN assisted tear-and-stack method. Also, our method can be used for twisted stack fabrication of materials that are few nanometers thick. Finally, we demonstrate the versatility of the tapered fibre scalpel for other shaping related applications for sensitive 2D materials.
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Affiliation(s)
- L D Varma Sangani
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
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Yin R, Ma L, Wang Z, Ma C, Chen X, Wang B. Reversible Superconductor-Insulator Transition in (Li, Fe)OHFeSe Flakes Visualized by Gate-Tunable Scanning Tunneling Spectroscopy. ACS NANO 2020; 14:7513-7519. [PMID: 32510920 DOI: 10.1021/acsnano.0c03289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Electric field control of charge carrier density provides a key in situ technology to continuously tune the ground states and map out the phase diagram of correlated electron systems in one device. This technique is highly expected to be combined with the modern state-of-the art spectroscopic probes, such as angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy (STM/S), to efficiently address these states and the underlying physics. However, it is extremely difficult and not successful so far, mainly because the fabrication process of such devices makes them prohibitive for surface probes. Here, by using a solid Li-ion conductor (SIC) as gate dielectric, we have successfully developed gate-tunable STM/S and visualized the superconductor-insulator transition (SIT) in a thin flake of single crystal (Li, Fe)OHFeSe at the nanoscale. The gate-controlled Li-ion injection first enhances the superconductivity and then drives the flake into an inhomogeneous insulating state, where superconductivity is totally suppressed. This process can be reversed by applying an opposite gate voltage. Importantly, the atomically resolved images allow us to identify the critical role that the injected Li ions play in the tuning process. Our results not only provide clear evidence of the microscopic mechanism of the tunable superconductivity and SIT in the SIC-based (Li, Fe)OHFeSe devices, but also establish SIC-gating STM as a powerful tool for investigating the complicated phase diagram of correlated electron system spectroscopically in a single sample with the field-effect approach.
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Affiliation(s)
- Ruoting Yin
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Likuan Ma
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Department of Physics, and CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Zhenyu Wang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Department of Physics, and CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Chuanxu Ma
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Xianhui Chen
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Department of Physics, and CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- CAS Center for Excellence in Quantum Information and Quantum Physics, Hefei, Anhui 230026, China
| | - Bing Wang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- CAS Center for Excellence in Quantum Information and Quantum Physics, Hefei, Anhui 230026, China
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Introducing Electrode Contact by Controlled Micro-Alloying in Few-Layered GaTe Field Effect Transistors. CRYSTALS 2020. [DOI: 10.3390/cryst10030144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recently, gallium telluride (GaTe) has triggered much attention for its unique properties and offers excellent opportunities for nanoelectronics. Yet it is a challenge to bridge the semiconducting few-layered GaTe crystals with metallic electrodes for device applications. Here, we report a method on fabricating electrode contacts to few-layered GaTe field effect transistors (FETs) by controlled micro-alloying. The devices show linear I-V curves and on/off ratio of ∼10 4 on HfO 2 substrates. Kelvin probe force microscope (KPFM) and energy dispersion spectrum (EDS) are performed to characterize the electrode contacts, suggesting that the lowered Schottky barrier by the diffusion of Pd element into the GaTe conduction channel may play an important role. Our findings provide a strategy for the engineering of electrode contact for future device applications based on 2DLMs.
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Film-thickness-driven superconductor to insulator transition in cuprate superconductors. Sci Rep 2020; 10:3236. [PMID: 32094455 PMCID: PMC7039923 DOI: 10.1038/s41598-020-60037-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 02/05/2020] [Indexed: 12/04/2022] Open
Abstract
The superconductor-insulator transition induced by film thickness control is investigated for the optimally doped cuprate superconductor La1.85Sr0.15CuO4. Epitaxial thin films are grown on an almost exactly matched substrate LaAlO3 (001). Despite the wide thickness range of 6 nm to 300 nm, all films are grown coherently without significant relaxation of the misfit strain. Electronic transport measurement exhibits systematic suppression of the superconducting phase by reducing the film thickness, thereby inducing a superconductor-insulator transition at a critical thickness of ~10 nm. The emergence of a resistance peak preceding the superconducting transition is discussed based on the weak localization. X-ray photoelectron spectroscopy results show the possibility that oxygen vacancies are present near the interface.
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Rafique M, Feng Z, Lin Z, Wei X, Liao M, Zhang D, Jin K, Xue QK. Ionic Liquid Gating Induced Protonation of Electron-Doped Cuprate Superconductors. NANO LETTERS 2019; 19:7775-7780. [PMID: 31664842 DOI: 10.1021/acs.nanolett.9b02776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Ion injection controlled by electric field has attracted growing attention due to its tunability over bulk-like materials. Here, we achieve protonation of an electron-doped high-temperature superconductor, La2-xCexCuO4, by gating in the electrochemical regime of the ionic liquid. Such a process induces a superconductor-insulator transition together with the crossing of the Fermi surface reconstruction point. Applying negative voltages not only can reverse the protonation process but also recovers superconductivity in samples deteriorated by moisture in the ambient. Our work extends the application of electric-field-induced protonation into high-temperature cuprate superconductors.
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Affiliation(s)
- Mohsin Rafique
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics , Tsinghua University , Beijing 100084 , China
| | - Zhongpei Feng
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Zefeng Lin
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Xinjian Wei
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Menghan Liao
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics , Tsinghua University , Beijing 100084 , China
| | - Ding Zhang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics , Tsinghua University , Beijing 100084 , China
- Beijing Academy of Quantum Information Sciences , Beijing 100193 , China
- Frontier Science Center for Quantum Information , Beijing 100084 , China
| | - Kui Jin
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Qi-Kun Xue
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics , Tsinghua University , Beijing 100084 , China
- Beijing Academy of Quantum Information Sciences , Beijing 100193 , China
- Frontier Science Center for Quantum Information , Beijing 100084 , China
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High-temperature superconductivity in monolayer Bi 2Sr 2CaCu 2O 8+δ. Nature 2019; 575:156-163. [PMID: 31666697 DOI: 10.1038/s41586-019-1718-x] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 08/23/2019] [Indexed: 11/09/2022]
Abstract
Although copper oxide high-temperature superconductors constitute a complex and diverse material family, they all share a layered lattice structure. This curious fact prompts the question of whether high-temperature superconductivity can exist in an isolated monolayer of copper oxide, and if so, whether the two-dimensional superconductivity and various related phenomena differ from those of their three-dimensional counterparts. The answers may provide insights into the role of dimensionality in high-temperature superconductivity. Here we develop a fabrication process that obtains intrinsic monolayer crystals of the high-temperature superconductor Bi2Sr2CaCu2O8+δ (Bi-2212; here, a monolayer refers to a half unit cell that contains two CuO2 planes). The highest superconducting transition temperature of the monolayer is as high as that of optimally doped bulk. The lack of dimensionality effect on the transition temperature defies expectations from the Mermin-Wagner theorem, in contrast to the much-reduced transition temperature in conventional two-dimensional superconductors such as NbSe2. The properties of monolayer Bi-2212 become extremely tunable; our survey of superconductivity, the pseudogap, charge order and the Mott state at various doping concentrations reveals that the phases are indistinguishable from those in the bulk. Monolayer Bi-2212 therefore displays all the fundamental physics of high-temperature superconductivity. Our results establish monolayer copper oxides as a platform for studying high-temperature superconductivity and other strongly correlated phenomena in two dimensions.
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Xu Y, Yu Y, Hui YY, Su Y, Cheng J, Chang HC, Zhang Y, Shen YR, Tian C. Mapping Dynamical Magnetic Responses of Ultrathin Micron-Size Superconducting Films Using Nitrogen-Vacancy Centers in Diamond. NANO LETTERS 2019; 19:5697-5702. [PMID: 31348663 DOI: 10.1021/acs.nanolett.9b02298] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Two-dimensional superconductors have attracted growing interest because of their scientific novelty, structural tunability, and useful properties. Studies of their magnetic responses, however, are often hampered by difficulties to grow large-size samples of high quality and uniformity. We report here an imaging method that employed NV- centers in diamond as a sensor capable of mapping out the microwave magnetic field distribution on an ultrathin superconducting film of micron size. Measurements on a 33 nm thick film and a 125 nm thick bulklike film of Bi2Sr2CaCu2O8+δ revealed that the alternating current (ac) Meissner effect (or repulsion of ac magnetic field) set in at 78 and 91 K, respectively; the latter was the superconducting transition temperature of both films. The unusual ac magnetic response of the thin film presumably was due to thermally excited vortex-antivortex diffusive motion in the film. Spatial resolution of our ac magnetometer was limited by optical diffraction and the noise level was at 14 μT/Hz1/2. The technique could be extended with better detection sensitivity to extract local ac conductivity/susceptibility of ultrathin or monolayer superconducting samples as well as ac magnetic responses of other two-dimensional exotic thin films of limited lateral size.
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Affiliation(s)
- Ying Xu
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
| | - Yijun Yu
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
| | - Yuen Yung Hui
- Institute of Atomic and Molecular Sciences , Academia Sinica , Taipei 10617 , Taiwan
| | - Yudan Su
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
| | - Jun Cheng
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
| | - Huan-Cheng Chang
- Institute of Atomic and Molecular Sciences , Academia Sinica , Taipei 10617 , Taiwan
| | - Yuanbo Zhang
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
- Collaborative Innovation Center of Advanced Microstructures , Nanjing 210093 , China
| | - Y Ron Shen
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
- Department of Physics , University of California , Berkeley , California 94720 , United States
| | - Chuanshan Tian
- Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro- and Nano-Photonic Structures (MOE) , Fudan University , Shanghai 200438 , China
- Collaborative Innovation Center of Advanced Microstructures , Nanjing 210093 , China
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