Orientation-dependent electronic structure in interfacial superconductors LaAlO 3 /KTaO 3 .

Autor: Chen X; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Yu T; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Liu Y; School of Physics, Zhejiang University, Hangzhou, China., Sun Y; School of Physics, Zhejiang University, Hangzhou, China., Lei M; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Guo N; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Fan Y; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Sun X; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Zhang M; School of Physics, Zhejiang University, Hangzhou, China., Alarab F; Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland., Strocov VN; Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland., Wang Y; School of Future Technology and Department of Physics, University of Science and Technology of China, Hefei, China., Zhou T; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Liu X; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Lu F; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Liu W; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China., Xie Y; School of Physics, Zhejiang University, Hangzhou, China. ywxie@zju.edu.cn., Peng R; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China. pengrui@fudan.edu.cn.; Shanghai Research Center for Quantum Sciences, Shanghai, China. pengrui@fudan.edu.cn., Xu H; Advanced Materials Laboratory, State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai, China. xuhaichao@fudan.edu.cn.; Shanghai Research Center for Quantum Sciences, Shanghai, China. xuhaichao@fudan.edu.cn., Feng D; National Synchrotron Radiation Laboratory and School of Nuclear Science and Technology, New Cornerstone Science Laboratory, University of Science and Technology of China, Hefei, China. dlfeng@ustc.edu.cn.; School of Emerging Technology and Department of Physics, University of Science and Technology of China, Hefei, China. dlfeng@ustc.edu.cn.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2024 Sep 04; Vol. 15 (1), pp. 7704. Date of Electronic Publication: 2024 Sep 04.
DOI: 10.1038/s41467-024-51969-4
Abstrakt: Emergent superconductivity at the LaAlO 3 /KTaO 3 interfaces exhibits a mysterious dependence on the KTaO 3 crystallographic orientations. Here by soft X-ray angle-resolved photoemission spectroscopy, we directly resolve the electronic structure of the LaAlO 3 /KTaO 3 interfacial superconductors and the non-superconducting counterpart. We find that the mobile electrons that contribute to the interfacial superconductivity show strong k ⊥ dispersion. Comparing the superconducting and non-superconducting interfaces, the quasi-three-dimensional electron gas with over 5.5 nm spatial distribution ubiquitously exists and shows similar orbital occupations. The signature of electron-phonon coupling is observed and intriguingly dependent on the interfacial orientations. Remarkably, the stronger electron-phonon coupling signature correlates with the higher superconducting transition temperature. Our observations help scrutinize the theories on the orientation-dependent superconductivity and offer a plausible and straightforward explanation. The interfacial orientation effect that can modify the electron-phonon coupling strength over several nanometers sheds light on the applications of oxide interfaces in general.
(© 2024. The Author(s).)
Databáze: MEDLINE
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