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Title: Dirac fermions in an antiferromagnetic semimetal

Abstract

Analogues of the elementary particles have been extensively searched for in condensed-matter systems for both scientific interest and technological applications. Recently, massless Dirac fermions were found to emerge as low-energy excitations in materials now known as Dirac semimetals. All of the currently known Dirac semimetals are non-magnetic with both time-reversal symmetry and inversion symmetry. Here in this paper, we show that Dirac fermions can exist in one type of antiferromagnetic system, where both and are broken but their combination is respected. We propose orthorhombic antiferromagnet CuMnAs as a candidate, analyse the robustness of the Dirac points under symmetry protections and demonstrate its distinctive bulk dispersions, as well as the corresponding surface states, by ab initio calculations. Our results provide a possible platform to study the interplay of Dirac fermion physics and magnetism.

Authors:
ORCiD logo [1]; ORCiD logo [1];  [1];  [1]
  1. Stanford Univ., CA (United States). Dept. of Physics
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1360178
Grant/Contract Number:
AC02-76SF00515; DMR-1305677
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Physics
Additional Journal Information:
Journal Volume: 12; Journal Issue: 12; Journal ID: ISSN 1745-2473
Publisher:
Nature Publishing Group (NPG)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Electronic properties and materials; Topological insulators

Citation Formats

Tang, Peizhe, Zhou, Quan, Xu, Gang, and Zhang, Shou-Cheng. Dirac fermions in an antiferromagnetic semimetal. United States: N. p., 2016. Web. doi:10.1038/NPHYS3839.
Tang, Peizhe, Zhou, Quan, Xu, Gang, & Zhang, Shou-Cheng. Dirac fermions in an antiferromagnetic semimetal. United States. doi:10.1038/NPHYS3839.
Tang, Peizhe, Zhou, Quan, Xu, Gang, and Zhang, Shou-Cheng. Mon . "Dirac fermions in an antiferromagnetic semimetal". United States. doi:10.1038/NPHYS3839. https://www.osti.gov/servlets/purl/1360178.
@article{osti_1360178,
title = {Dirac fermions in an antiferromagnetic semimetal},
author = {Tang, Peizhe and Zhou, Quan and Xu, Gang and Zhang, Shou-Cheng},
abstractNote = {Analogues of the elementary particles have been extensively searched for in condensed-matter systems for both scientific interest and technological applications. Recently, massless Dirac fermions were found to emerge as low-energy excitations in materials now known as Dirac semimetals. All of the currently known Dirac semimetals are non-magnetic with both time-reversal symmetry and inversion symmetry. Here in this paper, we show that Dirac fermions can exist in one type of antiferromagnetic system, where both and are broken but their combination is respected. We propose orthorhombic antiferromagnet CuMnAs as a candidate, analyse the robustness of the Dirac points under symmetry protections and demonstrate its distinctive bulk dispersions, as well as the corresponding surface states, by ab initio calculations. Our results provide a possible platform to study the interplay of Dirac fermion physics and magnetism.},
doi = {10.1038/NPHYS3839},
journal = {Nature Physics},
number = 12,
volume = 12,
place = {United States},
year = {Mon Aug 08 00:00:00 EDT 2016},
month = {Mon Aug 08 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 22works
Citation information provided by
Web of Science

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