金钯（=钪、钇且=铝、镓、铟）赫斯勒化合物是没有反演对称性的超导体吗？

Are AuPd ( = Sc, Y and = Al, Ga, In), Heusler Compounds Superconductors without Inversion Symmetry?

作者信息

Kautzsch Linus, Mende Felix, Fecher Gerhard H, Winterlik Jürgen, Felser Claudia

机构信息

Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany.

Johannes Gutenberg-Universität, Institut für Analytische Chemie und Anorganische Chemie, 55122 Mainz, Germany.

出版信息

Materials (Basel). 2019 Aug 13;12(16):2580. doi: 10.3390/ma12162580.

DOI:10.3390/ma12162580

PMID:31412638

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6719038/

Abstract

Heusler compounds with 2:1:1 stoichiometry either have a centrosymmetric Cu 2 MnAl structure or an Li 2 AgSb structure without a centre of inversion. The centrosymmetry is always lost in quaternary Heusler compounds with 1:1:1:1 stoichiometry and LiMgPdSn structure. This presents the possibility of realizing non-centrosymmetric superconductors in the family of Heusler compounds. The objective of this study is to search for and investigate such quaternary derivatives of Heusler compounds, particularly with respect to superconductivity. Several compounds were identified by carrying out calculations from first principles and superconductivity was observed in experiments conducted on AuPdScAl and AuPtScIn at the critical temperatures of 3.0 and 0.96 K, respectively. All investigated compounds had a valence electron count of 27, which is also the case in centrosymmetric Heusler superconductors.

摘要

化学计量比为2:1:1的赫斯勒化合物要么具有中心对称的Cu₂MnAl结构，要么具有无反演中心的Li₂AgSb结构。在化学计量比为1:1:1:1且具有LiMgPdSn结构的四元赫斯勒化合物中，中心对称性总是会丧失。这为在赫斯勒化合物家族中实现非中心对称超导体提供了可能性。本研究的目的是寻找并研究此类赫斯勒化合物的四元衍生物，特别是在超导性方面。通过第一性原理计算鉴定出了几种化合物，并且在分别针对AuPdScAl和AuPtScIn在3.0 K和0.96 K的临界温度下进行的实验中观察到了超导性。所有研究的化合物的价电子数均为27，中心对称的赫斯勒超导体也是如此。