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arXiv · 2011.08526

Observation of two-dimensional superconductivity at the LaAlO3/KTaO3(110) heterointerface

Zheng Chen·Zhongran Liu·Yanqiu Sun·Xiaoxin Chen·Yuan Liu·Hui Zhang·Hekang Li·Meng Zhang·Siyuan Hong·Tianshuang Ren·Chao Zhang·He Tian·Yi Zhou·Jirong Sun·Yanwu Xie
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Abstract

We report on the observation of a Tc ~0.9 K superconductivity at the interface between LaAlO3 film and the 5d transition-metal oxide KTaO3(110) single crystal. The interface shows a large anisotropy of the upper critical field, and its superconducting transition is consistent with a Berezinskii-Kosterlitz-Thouless transition. Both facts suggest that the superconductivity is two-dimensional (2D) in nature. The carrier density measured at 5 K is ~7 time 10^13 cm-2. The superconducting layer thickness and coherence length are estimated to be ~8 and ~30 nm, respectively. Our result provides a new platform for the study of 2D superconductivity at oxide interfaces.

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Zheng Chen, Zhongran Liu, Yanqiu Sun, Xiaoxin Chen, Yuan Liu, Hui Zhang, Hekang Li, Meng Zhang, Siyuan Hong, Tianshuang Ren, Chao Zhang, He Tian, Yi Zhou, Jirong Sun, Yanwu Xie. 2020-11-17. Observation of two-dimensional superconductivity at the LaAlO3/KTaO3(110) heterointerface. https://doi.org/10.1103/physrevlett.126.026802

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