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Fang H, Wang J, Nie F, Zhang N, Yu T, Zhao L, Shi C, Zhang P, He B, Lü W, Zheng L. Giant Electroresistance in Ferroelectric Tunnel Junctions via High-Throughput Designs: Toward High-Performance Neuromorphic Computing. ACS APPLIED MATERIALS & INTERFACES 2024; 16:1015-1024. [PMID: 38156871 DOI: 10.1021/acsami.3c13171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Ferroelectric tunnel junctions (FTJs) have been regarded as one of the most promising candidates for next-generation devices for data storage and neuromorphic computing owing to their advantages such as fast operation speed, low energy consumption, convenient 3D stack ability, etc. Here, dramatically different from the conventional engineering approaches, we have developed a tunnel barrier decoration strategy to improve the ON/OFF ratio, where the ultrathin SrTiO3 (STO) dielectric layers are periodically mounted onto the BaTiO3 (BTO) ferroelectric tunnel layer using the high-throughput technique. The inserted STO enhances the local tetragonality of the BTO, resulting in a strengthened ferroelectricity in the tunnel layer, which greatly improves the OFF state and reduces the ON state. Combined with the optimized oxygen migration, which can further manipulate the tunneling barrier, a record-high ON/OFF ratio of ∼108 has been achieved. Furthermore, utilizing these FTJ-based artificial synapses, an artificial neural network has been simulated via back-propagation algorithms, and a classification accuracy as high as 92% has been achieved. This study screens out the prominent FTJ by the high-throughput technique, advancing the tunnel layer decoration at the atomic level in the FTJ design and offering a fundamental understanding of the multimechanisms in the tunnel barrier.
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Affiliation(s)
- Hong Fang
- Functional Materials and Acousto-Optic Instruments Institute, School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150080, China
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Jie Wang
- Functional Materials and Acousto-Optic Instruments Institute, School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150080, China
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Fang Nie
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Nana Zhang
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Tongliang Yu
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Le Zhao
- School of Information and Automation Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Chaoqun Shi
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Peng Zhang
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Bin He
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Weiming Lü
- Functional Materials and Acousto-Optic Instruments Institute, School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150080, China
- Spintronics Institute, University of Jinan, Jinan 250022, China
| | - Limei Zheng
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
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2
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Shen JY, Shi CY, Pan ZM, Ju LL, Dong MD, Chen GF, Zhang YC, Yuan JK, Wu CJ, Xie YW, Wu J. Reentrance of interface superconductivity in a high-T c cuprate heterostructure. Nat Commun 2023; 14:7290. [PMID: 37949854 PMCID: PMC10638369 DOI: 10.1038/s41467-023-42903-1] [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: 05/13/2023] [Accepted: 10/25/2023] [Indexed: 11/12/2023] Open
Abstract
Increasing the carrier density in a Mott insulator by chemical doping gives rise to a generic superconducting dome in high temperature superconductors. An intriguing question is whether a second superconducting dome may exist at higher dopings. Here we heavily overdope La2-xSrxCuO4 (0.45 ≤ x ≤ 1.0) and discover an unprecedented reentrance of interface superconductivity in La2-xSrxCuO4 /La2CuO4 heterostructures. As x increases, the superconductivity is weakened and completely fades away at x = 0.8; but it revives at higher doping and fully recovers at x = 1.0. This is shown to be correlated with the suppression of the interfacial charge transfer around x = 0.8 and the weak-to-strong localization crossover in the La2-xSrxCuO4 layer. We further construct a theoretical model to account for the sophisticated relation between charge localization and interfacial charge transfer. Our work advances both the search for and control of new superconducting heterostructures.
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Affiliation(s)
- J Y Shen
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - C Y Shi
- School of Physics, Zhejiang University, Hangzhou, 310027, China
| | - Z M Pan
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
| | - L L Ju
- School of Physics, Zhejiang University, Hangzhou, 310027, China
| | - M D Dong
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - G F Chen
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - Y C Zhang
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - J K Yuan
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
| | - C J Wu
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
- New Cornerstone Science Laboratory, Department of Physics, School of Science, Westlake University, 310024, Hangzhou, China
- Institute for Theoretical Sciences, Westlake University, Hangzhou, 310024, Zhejiang, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, Zhejiang, China
| | - Y W Xie
- School of Physics, Zhejiang University, Hangzhou, 310027, China
| | - J Wu
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China.
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China.
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China.
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3
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Zhang L, Kang C, Liu C, Wang K, Zhang W. Two-dimensional superconducting nature of Bi 2Sr 2CaCu 2O 8+δ thin films revealed by BKT transition. RSC Adv 2023; 13:25797-25803. [PMID: 37664203 PMCID: PMC10468687 DOI: 10.1039/d3ra02701e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/15/2023] [Indexed: 09/05/2023] Open
Abstract
High-quality Bi2Sr2CaCu2O8+δ superconducting thin films are successfully grown on a SrTiO3 substrate by the Pulsed Laser Deposition technique. Superconducting critical transition temperatures Tc,zero have reached up to 85 K by using optimized growth parameters. In addition, we demonstrated the two-dimensional nature of the superconductivity of thin films by virtue of exhibiting Berezinskii-Kosterlitz-Thouless (BKT) physics and anisotropic magnetic response. Furthermore, three distinct regimes are identified based on the analysis of direct current resistance. The non-Fermi liquid phase and BKT phase fluctuation zone almost perfectly merge together, which implies that the system undergoes a unique topological state that is determined by the BKT phase fluctuation preceding the onset of the superconducting state. The emergence of such a topological state radically differentiates from the three-dimensional superconducting transition, which spontaneously breaks the gauge symmetry. The current studies on the Bi2Sr2CaCu2O8+δ superconducting thin films provide some new insights for understanding the rich quantum states of matter that emerge in the vicinity of the superconducting phase transition and highlight the significant role of BKT fluctuation on two-dimensional superconducting transition.
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Affiliation(s)
- Liping Zhang
- School of Future Technology, Henan University Zhengzhou 450046 China
| | - Chaoyang Kang
- School of Future Technology, Henan University Zhengzhou 450046 China
| | - Chengyan Liu
- School of Future Technology, Henan University Zhengzhou 450046 China
| | - Kai Wang
- Center for Topological Functional Materials, Henan University Kaifeng 475004 China
| | - Weifeng Zhang
- School of Future Technology, Henan University Zhengzhou 450046 China
- Institute of Quantum Materials and Physics, Henan Academy of Sciences Zhengzhou 450046 China
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4
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Meng M, Sun Y, Li Y, An Q, Wang Z, Lin Z, Yang F, Zhu X, Gao P, Guo J. Three dimensional band-filling control of complex oxides triggered by interfacial electron transfer. Nat Commun 2021; 12:2447. [PMID: 33907193 PMCID: PMC8079372 DOI: 10.1038/s41467-021-22790-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 03/29/2021] [Indexed: 11/09/2022] Open
Abstract
The d-band-filling of transition metals in complex oxides plays an essential role in determining their structural, electronic and magnetic properties. Traditionally, at the oxide heterointerface, band-filling control has been achieved via electrostatic modification in the structure of field-effect transistors or electron transfer, which is limited to the quasi-two-dimension at the interface. Here we report a three-dimensional (3D) band-filling control by changing the local lattice coordination in a designed oxide heterostructure. At the LaCoO3/LaTiO3 heterointerface, due to the Fermi level mismatch, electrons transfer from LaTiO3 to LaCoO3. This triggers destabilisation of the CoO6 octahedrons, i.e. the formation of lattice configurations with a reduced Co valence. The associated oxygen migration results in the 3D topotactic phase transition of LaCoO3. Tuned by the thickness of LaTiO3, different crystalline phases and band-fillings of Co occur, leading to the emergence of different magnetic ground states.
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Affiliation(s)
- Meng Meng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Yuanwei Sun
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
| | - Yuehui Li
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
| | - Qichang An
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Zhenzhen Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Zijian Lin
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Fang Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Xuetao Zhu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China.,Songshan Lake Materials Laboratory, Dongguan, Guangdong, China
| | - Peng Gao
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China. .,Collaborative Innovation Center of Quantum Matter, Beijing, China.
| | - Jiandong Guo
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China. .,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China. .,Songshan Lake Materials Laboratory, Dongguan, Guangdong, China. .,Beijing Academy of Quantum Information Sciences, Beijing, China.
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5
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Abstract
Superconductors with exotic physical properties are critical to current and future technology. In this review, we highlight several important superconducting families and focus on their crystal structure, chemical bonding, and superconductivity correlations. We connect superconducting materials with chemical bonding interactions based on their structure-property relationships, elucidating our empirically chemical approaches and other methods used in the discovery of new superconductors. Furthermore, we provide some technical strategies to synthesize superconductors and basic but important characterization for chemists needed when reporting new superconductors. In the end, we share our thoughts on how to make new superconductors and where chemists can work on in the superconductivity field. This review is written using chemical terms, with a focus on providing some chemically intuitive thoughts on superconducting materials design.
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Affiliation(s)
- Xin Gui
- Department of Chemistry, Princeton University, Princeton, New Jersey 08540, United States
| | - Bing Lv
- Department of Physics, University of Texas at Dallas, Richardson, Texas 75080, United States.,Department of Materials Science & Engineering, University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Weiwei Xie
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
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6
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Hao Z, Zou C, Luo X, Ji Y, Xu M, Ye S, Zhou X, Lin C, Wang Y. Anomalous Doping Evolution of Superconductivity and Quasiparticle Interference in Bi_{2}Sr_{2}Ca_{2}Cu_{3}O_{10+δ} Trilayer Cuprates. PHYSICAL REVIEW LETTERS 2020; 125:237005. [PMID: 33337206 DOI: 10.1103/physrevlett.125.237005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 11/02/2020] [Indexed: 06/12/2023]
Abstract
We use scanning tunneling microscopy to investigate Bi_{2}Sr_{2}Ca_{2}Cu_{3}O_{10+δ} trilayer cuprates from the optimally doped to overdoped regime. We find that the two distinct superconducting gaps from the inner and outer CuO_{2} planes both decrease rapidly with doping, in sharp contrast to the nearly constant T_{C}. Spectroscopic imaging reveals the absence of quasiparticle interference in the antinodal region of overdoped samples, showing an opposite trend to that in single- and double-layer compounds. We propose that the existence of two types of inequivalent CuO_{2} planes and the intricate interaction between them are responsible for these anomalies in trilayer cuprates.
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Affiliation(s)
- Zhenqi Hao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Changwei Zou
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Xiangyu Luo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Yu Ji
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Miao Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Shusen Ye
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Xingjiang Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Chengtian Lin
- Max Planck Institute for Solid State Research, Heisenbergstr 1, D-70569 Stuttgart, Germany
| | - Yayu Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
- Frontier Science Center for Quantum Information, Beijing 100084, People's Republic of China
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7
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Zhong Y, Fan JQ, Wang RF, Wang S, Zhang X, Zhu Y, Dou Z, Yu XQ, Wang Y, Zhang D, Zhu J, Song CL, Ma XC, Xue QK. Direct Visualization of Ambipolar Mott Transition in Cuprate CuO_{2} Planes. PHYSICAL REVIEW LETTERS 2020; 125:077002. [PMID: 32857570 DOI: 10.1103/physrevlett.125.077002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/24/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Identifying the essence of doped Mott insulators is one of the major outstanding problems in condensed matter physics and the key to understanding the high-temperature superconductivity in cuprates. We report real space visualization of Mott insulator-metal transition in Sr_{1-x}La_{x}CuO_{2+y} cuprate films that cover both the electron- and hole-doped regimes. Tunneling conductance measurements directly on the copper-oxide (CuO_{2}) planes reveal a systematic shift in the Fermi level, while the fundamental Mott-Hubbard band structure remains unchanged. This is further demonstrated by exploring the atomic-scale electronic response of CuO_{2} to substitutional dopants and intrinsic defects in a sister compound Sr_{0.92}Nd_{0.08}CuO_{2}. The results may be better explained in the framework of self-modulation doping, similar to that in semiconductor heterostructures, and form a basis for developing any microscopic theories for cuprate superconductivity.
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Affiliation(s)
- Yong Zhong
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Jia-Qi Fan
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Rui-Feng Wang
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - ShuZe Wang
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Xuefeng Zhang
- Institute of Physics, National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Yuying Zhu
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Ziyuan Dou
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Xue-Qing Yu
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Yang Wang
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Ding Zhang
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
| | - Jing Zhu
- Institute of Physics, National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Can-Li Song
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
| | - Xu-Cun Ma
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
| | - Qi-Kun Xue
- State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
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8
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He G, Wei Z, Feng Z, Yu X, Zhu B, Liu L, Jin K, Yuan J, Huan Q. Combinatorial laser molecular beam epitaxy system integrated with specialized low-temperature scanning tunneling microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:013904. [PMID: 32012528 DOI: 10.1063/1.5119686] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 12/19/2019] [Indexed: 06/10/2023]
Abstract
We present a newly developed facility comprising a combinatorial laser molecular beam epitaxy system and an in situ scanning tunneling microscope (STM). This facility aims at accelerating the materials research in a highly efficient way by advanced high-throughput film synthesis techniques and subsequent fast characterization of surface morphology and electronic states. Compared with uniform films deposited by conventional methods, the so-called combinatorial thin films will be beneficial in determining the accurate phase diagrams of different materials due to the improved control of parameters such as chemical substitution and sample thickness resulting from a rotary-mask method. A specially designed STM working under low-temperature and ultrahigh vacuum conditions is optimized for the characterization of combinatorial thin films in an XY coarse motion range of 15 mm × 15 mm with submicrometer location precision. The overall configuration and some key aspects such as the sample holder design, scanner head, and sample/tip/target transfer mechanism are described in detail. The performance of the device is demonstrated by synthesizing high-quality superconducting FeSe thin films with gradient thickness and imaging surfaces of highly oriented pyrolytic graphite, Au (111), Bi2Sr2CaCu2O8+δ (BSCCO), and FeSe. In addition, we also have obtained clean noise spectra of tunneling junctions and the superconducting energy gap of BSCCO. The successful manufacturing of such a facility opens a new window for the next generation equipment designed for experimental materials research.
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Affiliation(s)
- Ge He
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhongxu Wei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhongpei Feng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiaodong Yu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Beiyi Zhu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Li Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Kui Jin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Jie Yuan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Qing Huan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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9
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Choi EM, Di Bernardo A, Zhu B, Lu P, Alpern H, Zhang KHL, Shapira T, Feighan J, Sun X, Robinson J, Paltiel Y, Millo O, Wang H, Jia Q, MacManus-Driscoll JL. 3D strain-induced superconductivity in La 2CuO 4+δ using a simple vertically aligned nanocomposite approach. SCIENCE ADVANCES 2019; 5:eaav5532. [PMID: 31032414 PMCID: PMC6486216 DOI: 10.1126/sciadv.aav5532] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 03/07/2019] [Indexed: 05/28/2023]
Abstract
A long-term goal for superconductors is to increase the superconducting transition temperature, T C. In cuprates, T C depends strongly on the out-of-plane Cu-apical oxygen distance and the in-plane Cu-O distance, but there has been little attention paid to tuning them independently. Here, in simply grown, self-assembled, vertically aligned nanocomposite thin films of La2CuO4+δ + LaCuO3, by strongly increasing out-of-plane distances without reducing in-plane distances (three-dimensional strain engineering), we achieve superconductivity up to 50 K in the vertical interface regions, spaced ~50 nm apart. No additional process to supply excess oxygen, e.g., by ozone or high-pressure oxygen annealing, was required, as is normally the case for plain La2CuO4+δ films. Our proof-of-concept work represents an entirely new approach to increasing T C in cuprates or other superconductors.
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Affiliation(s)
- Eun-Mi Choi
- Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK
| | - Angelo Di Bernardo
- Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK
| | - Bonan Zhu
- Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK
| | - Ping Lu
- Sandia National Laboratories, Albuquerque, NM 87185, USA
| | - Hen Alpern
- Racah Institute of Physics and Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Kelvin H. L. Zhang
- Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK
| | - Tamar Shapira
- Racah Institute of Physics and Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - John Feighan
- Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK
| | - Xing Sun
- Department of Materials Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Jason Robinson
- Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK
| | - Yossi Paltiel
- Department of Applied Physics and Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Oded Millo
- Racah Institute of Physics and Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Haiyan Wang
- Department of Materials Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Quanxi Jia
- Department of Materials Design and Innovation, University at Buffalo—The State University of New York, Buffalo, NY, USA
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10
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Aslam M, Singh CK, Das S, Kumar R, Datta S, Halder S, Gayen S, Kabir M, Sheet G. Large enhancement of superconductivity in Zr point contacts. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:255002. [PMID: 29708502 DOI: 10.1088/1361-648x/aac154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
For certain complex superconducting systems, the superconducting properties get enhanced under mesoscopic point contacts made of elemental non-superconducting metals. However, understanding of the mechanism through which such contact induced local enhancement of superconductivity happens has been limited due to the complex nature of such compounds. In this paper we present a large enhancement of superconducting transition temperature T c and superconducting energy gap Δ in a simple elemental superconductor Zr. While bulk Zr shows a critical temperature around 0.6 K, superconductivity survives at Ag/Zr and Pt/Zr point contacts up to 3 K with a corresponding five-fold enhancement of Δ. Further, the first-principles calculations on a model system provide useful insights. We show that the enhancement in superconducting properties can be attributed to a modification in the electron-phonon coupling accompanied by an enhancement of the density of states which involves the appearance of a new electron band at the Ag/Zr interfaces.
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Affiliation(s)
- Mohammad Aslam
- Department of Physical Sciences, Indian Institute of Science Education and Research, Mohali 140306, India
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11
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Baiutti F, Gregori G, Suyolcu YE, Wang Y, Cristiani G, Sigle W, van Aken PA, Logvenov G, Maier J. High-temperature superconductivity at the lanthanum cuprate/lanthanum-strontium nickelate interface. NANOSCALE 2018; 10:8712-8720. [PMID: 29701210 DOI: 10.1039/c8nr00885j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The utilization of interface effects in epitaxial systems at the nanoscale has emerged as a very powerful approach for engineering functional properties of oxides. Here we present a novel structure fabricated by a state-of-the-art oxide molecular beam epitaxy method and consisting of lanthanum cuprate and strontium (Sr)-doped lanthanum nickelate, in which interfacial high-temperature superconductivity (Tc up to 40 K) occurs at the contact between the two phases. In such a system, we are able to tune the superconducting properties simply by changing the structural parameters. By employing electron spectroscopy and microscopy combined with dedicated conductivity measurements, we show that decoupling occurs between the electronic charge carrier and the cation (Sr) concentration profiles at the interface and that a hole accumulation layer forms, which dictates the resulting superconducting properties. Such effects are rationalized in the light of a generalized space-charge theory for oxide systems that takes account of both ionic and electronic redistribution effects.
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Affiliation(s)
- F Baiutti
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany.
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Frustration-driven C 4 symmetric order in a naturally-heterostructured superconductor Sr 2VO 3FeAs. Nat Commun 2017; 8:2167. [PMID: 29255140 PMCID: PMC5735138 DOI: 10.1038/s41467-017-02327-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 11/15/2017] [Indexed: 11/08/2022] Open
Abstract
A subtle balance between competing interactions in iron-based superconductors (FeSCs) can be tipped by additional interfacial interactions in a heterostructure, often inducing exotic phases with unprecedented properties. Particularly when the proximity-coupled layer is magnetically active, rich phase diagrams are expected in FeSCs, but this has not been explored yet. Here, using high-accuracy 75As and 51V nuclear magnetic resonance measurements, we investigate an electronic phase that emerges in the FeAs layer below T 0 ~ 155 K of Sr2VO3FeAs, a naturally assembled heterostructure of an FeSC and a Mott-insulating vanadium oxide. We find that frustration of the otherwise dominant Fe stripe and V Neel fluctuations via interfacial coupling induces a charge/orbital order in the FeAs layers, without either static magnetism or broken C 4 symmetry, while suppressing the Neel antiferromagnetism in the SrVO3 layers. These findings demonstrate that the magnetic proximity coupling stabilizes a hidden order in FeSCs, which may also apply to other strongly correlated heterostructures.
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13
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Wu J, Bollinger AT, He X, Božović I. Spontaneous breaking of rotational symmetry in copper oxide superconductors. Nature 2017; 547:432-435. [DOI: 10.1038/nature23290] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 06/08/2017] [Indexed: 11/09/2022]
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14
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Suyolcu YE, Wang Y, Baiutti F, Al-Temimy A, Gregori G, Cristiani G, Sigle W, Maier J, van Aken PA, Logvenov G. Dopant size effects on novel functionalities: High-temperature interfacial superconductivity. Sci Rep 2017; 7:453. [PMID: 28352070 PMCID: PMC5428683 DOI: 10.1038/s41598-017-00539-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 02/28/2017] [Indexed: 12/03/2022] Open
Abstract
Among the range of complex interactions, especially at the interfaces of epitaxial oxide systems, contributing to the occurrence of intriguing effects, a predominant role is played by the local structural parameters. In this study, oxide molecular beam epitaxy grown lanthanum cuprate-based bilayers (consisting of a metallic (M) and an insulating phase (I)), in which high-temperature superconductivity arises as a consequence of interface effects, are considered. With the aim of assessing the role of the dopant size on local crystal structure and chemistry, and on the interface functionalities, different dopants (Ca2+, Sr2+ and, Ba2+) are employed in the M-phase, and the M–I bilayers are investigated by complementary techniques, including spherical-aberration-corrected scanning transmission electron microscopy. A series of exciting outcomes are found: (i) the average out-of-plane lattice parameter of the bilayers is linearly dependent on the dopant ion size, (ii) each dopant redistributes at the interface with a characteristic diffusion length, and (iii) the superconductivity properties are highly dependent on the dopant of choice. Hence, this study highlights the profound impact of the dopant size and related interface chemistry on the functionalities of superconducting oxide systems.
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Affiliation(s)
- Y Eren Suyolcu
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany.
| | - Yi Wang
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Federico Baiutti
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Ameer Al-Temimy
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany.,Al-Nahrain Nanorenewable Energy Research Center, Al-Nahrain University, Baghdad, Iraq
| | - Giuliano Gregori
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Georg Cristiani
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Wilfried Sigle
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Joachim Maier
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Peter A van Aken
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
| | - Gennady Logvenov
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany
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Oxygen Displacement in Cuprates under Ionic Liquid Field-Effect Gating. Sci Rep 2016; 6:32378. [PMID: 27578237 PMCID: PMC5006154 DOI: 10.1038/srep32378] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 08/02/2016] [Indexed: 11/20/2022] Open
Abstract
We studied structural changes in a 5 unit cell thick La1.96Sr0.04CuO4 film, epitaxially grown on a LaSrAlO4 substrate with a single unit cell buffer layer, when ultra-high electric fields were induced in the film by applying a gate voltage between the film (ground) and an ionic liquid in contact with it. Measuring the diffraction intensity along the substrate-defined Bragg rods and analyzing the results using a phase retrieval method we obtained the three-dimensional electron density in the film, buffer layer, and topmost atomic layers of the substrate under different applied gate voltages. The main structural observations were: (i) there were no structural changes when the voltage was negative, holes were injected into the film making it more metallic and screening the electric field; (ii) when the voltage was positive, the film was depleted of holes becoming more insulating, the electric field extended throughout the film, the partial surface monolayer became disordered, and equatorial oxygen atoms were displaced towards the surface; (iii) the changes in surface disorder and the oxygen displacements were both reversed when a negative voltage was applied; and (iv) the c-axis lattice constant of the film did not change in spite of the displacement of equatorial oxygen atoms.
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16
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Dependence of the critical temperature in overdoped copper oxides on superfluid density. Nature 2016; 536:309-11. [DOI: 10.1038/nature19061] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 06/16/2016] [Indexed: 11/08/2022]
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17
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Leng X, Bollinger AT, Božović I. Purely electronic mechanism of electrolyte gating of indium tin oxide thin films. Sci Rep 2016; 6:31239. [PMID: 27506371 PMCID: PMC4979031 DOI: 10.1038/srep31239] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 07/15/2016] [Indexed: 11/21/2022] Open
Abstract
Epitaxial indium tin oxide films have been grown on both LaAlO3 and yttria-stabilized zirconia substrates using RF magnetron sputtering. Electrolyte gating causes a large change in the film resistance that occurs immediately after the gate voltage is applied, and shows no hysteresis during the charging/discharging processes. When two devices are patterned next to one another and the first one gated through an electrolyte, the second one shows no changes in conductance, in contrast to what happens in materials (like tungsten oxide) susceptible to ionic electromigration and intercalation. These findings indicate that electrolyte gating in indium tin oxide triggers a pure electronic process (electron depletion or accumulation, depending on the polarity of the gate voltage), with no electrochemical reactions involved. Electron accumulation occurs in a very thin layer near the film surface, which becomes highly conductive. These results contribute to our understanding of the electrolyte gating mechanism in complex oxides and may be relevant for applications of electric double layer transistor devices.
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Affiliation(s)
- X Leng
- Brookhaven National Laboratory, Upton NY 11973, USA
| | | | - I Božović
- Brookhaven National Laboratory, Upton NY 11973, USA.,Applied Physics Department, Yale University, New Haven CT 06520, USA
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Misawa T, Nomura Y, Biermann S, Imada M. Self-optimized superconductivity attainable by interlayer phase separation at cuprate interfaces. SCIENCE ADVANCES 2016; 2:e1600664. [PMID: 27482542 PMCID: PMC4966878 DOI: 10.1126/sciadv.1600664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 06/29/2016] [Indexed: 06/06/2023]
Abstract
Stabilizing superconductivity at high temperatures and elucidating its mechanism have long been major challenges of materials research in condensed matter physics. Meanwhile, recent progress in nanostructuring offers unprecedented possibilities for designing novel functionalities. Above all, thin films of cuprate and iron-based high-temperature superconductors exhibit remarkably better superconducting characteristics (for example, higher critical temperatures) than in the bulk, but the underlying mechanism is still not understood. Solving microscopic models suitable for cuprates, we demonstrate that, at an interface between a Mott insulator and an overdoped nonsuperconducting metal, the superconducting amplitude is always pinned at the optimum achieved in the bulk, independently of the carrier concentration in the metal. This is in contrast to the dome-like dependence in bulk superconductors but consistent with the astonishing independence of the critical temperature from the carrier density x observed at the interfaces of La2CuO4 and La2-x Sr x CuO4. Furthermore, we identify a self-organization mechanism as responsible for the pinning at the optimum amplitude: An emergent electronic structure induced by interlayer phase separation eludes bulk phase separation and inhomogeneities that would kill superconductivity in the bulk. Thus, interfaces provide an ideal tool to enhance and stabilize superconductivity. This interfacial example opens up further ways of shaping superconductivity by suppressing competing instabilities, with direct perspectives for designing devices.
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Affiliation(s)
- Takahiro Misawa
- Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yusuke Nomura
- Centre de Physique Théorique, École Polytechnique, CNRS, Université Paris-Saclay, F-91128 Palaiseau, France
| | - Silke Biermann
- Centre de Physique Théorique, École Polytechnique, CNRS, Université Paris-Saclay, F-91128 Palaiseau, France
| | - Masatoshi Imada
- Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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19
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Abstract
Upon doping, cuprates undergo a quantum phase transition from an insulator to a d-wave superconductor. The nature of this transition and of the insulating state is vividly debated. Here, we study the Hall effect in La2-xSrxCuO4(LSCO) samples doped near the quantum critical point atx∼ 0.06. Dramatic fluctuations in the Hall resistance appear belowTCG∼ 1.5 K and increase as the sample is cooled down further, signaling quantum critical behavior. We explore the doping dependence of this effect in detail, by studying a combinatorial LSCO library in which the Sr content is varied in extremely fine steps,Δx∼ 0.00008. We observe that quantum charge fluctuations wash out when superconductivity emerges but can be restored when the latter is suppressed by applying a magnetic field, showing that the two instabilities compete for the ground state.
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Wang Y, Baiutti F, Gregori G, Cristiani G, Salzberger U, Logvenov G, Maier J, van Aken PA. Atomic-Scale Quantitative Analysis of Lattice Distortions at Interfaces of Two-Dimensionally Sr-Doped La2CuO4 Superlattices. ACS APPLIED MATERIALS & INTERFACES 2016; 8:6763-6769. [PMID: 26909681 PMCID: PMC4796864 DOI: 10.1021/acsami.5b12813] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 02/24/2016] [Indexed: 06/05/2023]
Abstract
Using spherical aberration corrected high-resolution and analytical scanning transmission electron microscopy, we have quantitatively studied the lattice distortion and the redistribution of charges in two-dimensionally strontium (Sr)-doped La2CuO4 superlattices, in which single LaO planes are periodically replaced by SrO planes. As shown previously, such structures show Tc up to 35 K as a consequence of local charge accumulation on both sides of the nominal SrO planes position. This is caused by two distinct mechanisms of doping: heterogeneous doping at the downward side of the interface (space-charge effect) and "classical" homogeneous doping at the upward side. The comparative chemical and atomic-structural analyses reveal an interrelation between local CuO6 octahedron distortions, hole spatial distribution, and chemical composition. In particular we observe an anomalous expansion of the apical oxygen-oxygen distance in the heterogeneously doped (space-charge) region, and a substantial shrinkage of the apical oxygen-oxygen distance in the homogeneously doped region. Such findings are interpreted in terms of different Jahn-Teller effects occurring at the two interface sides (downward and upward).
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Boschker H, Richter C, Fillis-Tsirakis E, Schneider CW, Mannhart J. Electron-phonon Coupling and the Superconducting Phase Diagram of the LaAlO3-SrTiO3 Interface. Sci Rep 2015; 5:12309. [PMID: 26169351 PMCID: PMC4648410 DOI: 10.1038/srep12309] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 06/25/2015] [Indexed: 12/03/2022] Open
Abstract
The superconductor at the LaAlO3—SrTiO3 interface provides a model system for the study of two-dimensional superconductivity in the dilute carrier density limit. Here we experimentally address the pairing mechanism in this superconductor. We extract the electron—phonon spectral function from tunneling spectra and conclude, without ruling out contributions of further pairing channels, that electron—phonon mediated pairing is strong enough to account for the superconducting critical temperatures. Furthermore, we discuss the electron—phonon coupling in relation to the superconducting phase diagram. The electron—phonon spectral function is independent of the carrier density, except for a small part of the phase diagram in the underdoped region. The tunneling measurements reveal that the increase of the chemical potential with increasing carrier density levels off and is zero in the overdoped region of the phase diagram. This indicates that the additionally induced carriers do not populate the band that hosts the superconducting state and that the superconducting order parameter therefore is weakened by the presence of charge carriers in another band.
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Affiliation(s)
- Hans Boschker
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
| | - Christoph Richter
- 1] Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany [2] Center for Electronic Correlations and Magnetism, Augsburg University, 86135 Augsburg, Germany
| | | | | | - Jochen Mannhart
- Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany
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22
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Superconductivity and its mechanism in an ab initio model for electron-doped LaFeAsO. Nat Commun 2014; 5:5738. [DOI: 10.1038/ncomms6738] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 11/02/2014] [Indexed: 11/08/2022] Open
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23
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Baiutti F, Christiani G, Logvenov G. Towards precise defect control in layered oxide structures by using oxide molecular beam epitaxy. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:596-602. [PMID: 24995148 PMCID: PMC4079053 DOI: 10.3762/bjnano.5.70] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 04/10/2014] [Indexed: 06/03/2023]
Abstract
In this paper we present the atomic-layer-by-layer oxide molecular beam epitaxy (ALL-oxide MBE) which has been recently installed in the Max-Planck Institute for Solid State Research and we report on its present status, providing some examples that demonstrate its successful application in the synthesis of different layered oxides, with particular reference to superconducting La2CuO4 and insulator-to-metal La2- x Sr x NiO4. We briefly review the ALL-oxide MBE technique and its unique capabilities in the deposition of atomically smooth single-crystal thin films of various complex oxides, artificial compounds and heterostructures, introducing our goal of pursuing a deep investigation of such systems with particular emphasis on structural defects, with the aim of tailoring their functional properties by precise defects control.
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Affiliation(s)
- Federico Baiutti
- Max-Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569, Stuttgart, Germany
| | - Georg Christiani
- Max-Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569, Stuttgart, Germany
| | - Gennady Logvenov
- Max-Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569, Stuttgart, Germany
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van der Marel D. Interface superconductivity: Pinning the critical temperature. NATURE MATERIALS 2013; 12:875-876. [PMID: 24056853 DOI: 10.1038/nmat3761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- Dirk van der Marel
- Département de Physique de la Matière Condensée, 24 quai Ernest-Ansermet, CH-1211 Genève 4, Switzerland
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