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arXiv · 1811.12213

Superconductivity Induced at a Point Contact on the Topological Semimetal Tungsten Carbide

Xing-yuan Hou·Zong Wang·Ya-dong Gu·Jun-bao He·Dong Chen·Wen-liang Zhu·Meng-di Zhang·Yuan-feng Xu·Zhi-an Ren·Hong-ming Weng·Ning Hao·Wen-gang Lv·Jiang-ping Hu·Gen-fu Chen·Lei Shan
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Abstract

We report the observation of local superconductivity induced at the point contact formed between a normal metal tip and WC -- a triple point topological semimetal with super hardness. Remarkably, the maximum critical temperature is up to near 12 K but insensitive to the tip's magnetism. The lateral dimensions of the superconducting puddles were evaluated and the temperature dependencies of superconducting gap and upper critical field were also obtained. These results put constraints on the explanation of the induced superconductivity and pave a pathway for exploring topological superconductivity.

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Xing-yuan Hou, Zong Wang, Ya-dong Gu, Jun-bao He, Dong Chen, Wen-liang Zhu, Meng-di Zhang, Yuan-feng Xu, Zhi-an Ren, Hong-ming Weng, Ning Hao, Wen-gang Lv, Jiang-ping Hu, Gen-fu Chen, Lei Shan. 2019-09-27. Superconductivity Induced at a Point Contact on the Topological Semimetal Tungsten Carbide. https://doi.org/10.1103/physrevb.100.235109

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