超越狄拉克与外尔费米子:常规晶体中的非传统准粒子
介观与纳米尺度物理
2016-07-25 v3 材料科学
强关联电子
摘要
在量子场论中,我们得知费米子有三种:马约拉纳、外尔和狄拉克。在此我们表明,在固态系统中这种分类是不完备的,并发现了几种额外的晶体对称性保护自由费米子激发。我们详尽分类了在具有自旋轨道耦合和时间反演对称性的固态系统中,由空间群对称性稳定的线性与二次 3、6 和 8 能带交叉。出现了几种不同类型的费米子,它们由在高对称点、线和面上的简并度区分。这些费米子的一些显著后果是非外尔系统中费米弧的存在以及狄拉克线的存在。第一性原理计算确定了若干在费米能级附近实现这些奇异费米子的材料。
引用
@article{arxiv.1603.03093,
title = {Beyond Dirac and Weyl fermions: Unconventional quasiparticles in conventional crystals},
author = {Barry Bradlyn and Jennifer Cano and Zhijun Wang and M. G. Vergniory and C. Felser and R. J. Cava and B. Andrei Bernevig},
journal= {arXiv preprint arXiv:1603.03093},
year = {2016}
}
备注
v1: main text 9pgs. 29pg supplementary material. Submitted on 2/18/2016 v2: 2 new authors and 19 new materials added. Discussion of 4-band spin-3/2 fermions added, with emphasis on overlap with other materials of interest. Discussion of Zeeman splitting and other experimental implications added. v3: Accepted version. Minor typos fixed, title changed (formerly "New fermions"). Now 10+41pgs