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arXiv · 1607.02886

Reply to Comment on "Tip induced unconventional superconductivity on Weyl semimetal TaAs"

Abstract

Recently, we presented a paper about the tip-induced superconducting phase on TaAs single crystal (arXiv:1607.00513). A conductance plateau with double conductance peaks at finite bias, sharp double dips and a zero bias conductance peak were observed in the point contact spectra (PCS). These three features in one PCS suggest the possibility of p-wave like superconductivity and Majorana zero modes in the surface. Soon after our paper posted on arXiv, Gayen el al. (arXiv:1607.01405) questioned the underlying mechanism of our observations based on their experimental measurements in conventional superconductors(Pb and Nb) and conclusively indicated that the superconductivity observed in our TaAs crystal is conventional. We disagree with their quick conclusion without any specific study on the TaAs materials. We will explain in the following that for the clean (Z=0) point contact (PC) in ballistic limit, the superconducting transition feature in temperature dependence of PC resistance is expected. And the critical current effect claimed by Gayen el al. cannot explain the observed PCS in our paper.

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He Wang, Huichao Wang, Yuqin Chen, Jiawei Luo, Zhujun Yuan, Jun Liu, Yong Wang, Shuang Jia, Xiong-Jun Liu, Jian Wei, Jian Wang. 2016-07-11. Reply to Comment on "Tip induced unconventional superconductivity on Weyl semimetal TaAs". https://arxiv.org/abs/1607.02886

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