Two-dimensional superconductivity and anisotropic transport at KTaO <sub>3</sub> (111) interfaces
Changjiang Liu, Xi Yan, Dafei Jin, Yang Ma, Haw-Wen Hsiao, Yulin Lin, Terence Bretz-Sullivan, Xianjing Zhou, John E. Pearson, Brandon Fisher, J. S. Jiang, Wei Han, Jian‐Min Zuo, Jianguo Wen, Dillon D. Fong, Jirong Sun, Hua Zhou, Anand Bhattacharya
Abstract
A superconducting interface Interfaces between materials can harbor quantum states that belong to neither of the materials. A classic example is the superconducting interface between two insulating oxides, LaAlO 3 and SrTiO 3 , with a critical temperature of around 200 millikelvin. Liu et al. observed superconductivity at a different interface—formed between KTaO 3 as a substrate and an overlayer of either EuO or LaAlO 3 —at a considerably higher temperature of about 2 kelvin. Transport measurements displayed anisotropy, which may indicate an unusual superconducting state. Science , this issue p. 716