Investigation of point-contact Andreev reflection on magnetic Weyl semimetal Co3Sn2S2  

作　　者：He Wang YanZhao Liu HuiBin Zhou HaoRan Ji JiaWei Luo JiaWei Zhang TianHeng Wei PinYuan Wang Shuang Jia Jian Wang 

机构地区：[1]Department of Physics,Capital Normal University,Beijing 100048,China [2]International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China [3]Collaborative Innovation Center of Quantum Matter,Beijing 100871,China [4]CAS Center for Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing 100190,China [5]Beijing Academy of Quantum Information Sciences,Beijing 100193,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2020年第8期107-113,共7页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Key R&D Program of China(Grant Nos.2018YFA0305600,and 2017YFA0303302);the National Natural Science Foundation of China(Grant Nos.11888101,11774008,11774007,U1832214,and 11704279);the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB28000000);the Beijing Natural Science Foundation(Grant Nos.Z180010,and 1202005)。

摘　　要：Magnetic Weyl semimetals(WSMs)with broken time-reversal symmetry(TRS)hosting topological band structures are expected to provide an ideal platform for investigating topological superconductivity and spintronics.However,the experimental verification of magnetic WSMs is very challenging.Very recently,the kagome magnet Co3Sn2S2 was confirmed to be a magnetic WSM by both angle-resolved photoemission spectroscopy and scanning tunneling spectroscopy and consequently has become the focus of great attention.This paper reports a point-contact Andreev-reflection spectroscopy(PCARS)investigation on the(001)surface and the side surface of the Co3Sn2S2 single crystals,respectively.The measurements from the sample’s(001)and side surfaces provide experimental evidence for transport spin polarization in the Co3Sn2S2 magnetic WSM.Furthermore,the superconducting proximity effect in the Co3Sn2S2 single crystal is successfully detected.The point-contact spectra(PCS)along the in-plane direction cannot be well fitted by theoretical models based on s-wave pairing,indicating that possible triplet p-wave superconductivity may be triggered at the interface,which paves the way for the future exploration of the topological superconductivity and Majorana states in broken TRS WSMs.

关 键 词：magnetic Weyl semimetal point contact pairing symmetry superconducting proximity effect 

分 类 号：O469[理学—凝聚态物理]