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Title: Symmetry-Enforced Line Nodes in Unconventional Superconductors [Nodal-Line Superconductors and Band-Sticking]

Abstract

We classify line nodes in superconductors with strong spin-orbit interactions and time-reversal symmetry, where the latter may include nonprimitive translations in the magnetic Brillouin zone to account for coexistence with antiferromagnetic order. We find four possible combinations of irreducible representations of the order parameter on high-symmetry planes, two of which allow for line nodes in pseudospin-triplet pairs and two that exclude conventional fully gapped pseudospin-singlet pairs. We show that the former can only be realized in the presence of band-sticking degeneracies, and we verify their topological stability using arguments based on Clifford algebra extensions. Lastly, our classification exhausts all possible symmetry protected line nodes in the presence of spin-orbit coupling and a (generalized) time-reversal symmetry. Implications for existing nonsymmorphic and antiferromagnetic superconductors are discussed.

Authors:
 [1];  [2]
  1. Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro (Brazil)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1374185
Alternate Identifier(s):
OSTI ID: 1357855
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 20; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Micklitz, T., and Norman, M. R. Symmetry-Enforced Line Nodes in Unconventional Superconductors [Nodal-Line Superconductors and Band-Sticking]. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.207001.
Micklitz, T., & Norman, M. R. Symmetry-Enforced Line Nodes in Unconventional Superconductors [Nodal-Line Superconductors and Band-Sticking]. United States. doi:10.1103/PhysRevLett.118.207001.
Micklitz, T., and Norman, M. R. Thu . "Symmetry-Enforced Line Nodes in Unconventional Superconductors [Nodal-Line Superconductors and Band-Sticking]". United States. doi:10.1103/PhysRevLett.118.207001. https://www.osti.gov/servlets/purl/1374185.
@article{osti_1374185,
title = {Symmetry-Enforced Line Nodes in Unconventional Superconductors [Nodal-Line Superconductors and Band-Sticking]},
author = {Micklitz, T. and Norman, M. R.},
abstractNote = {We classify line nodes in superconductors with strong spin-orbit interactions and time-reversal symmetry, where the latter may include nonprimitive translations in the magnetic Brillouin zone to account for coexistence with antiferromagnetic order. We find four possible combinations of irreducible representations of the order parameter on high-symmetry planes, two of which allow for line nodes in pseudospin-triplet pairs and two that exclude conventional fully gapped pseudospin-singlet pairs. We show that the former can only be realized in the presence of band-sticking degeneracies, and we verify their topological stability using arguments based on Clifford algebra extensions. Lastly, our classification exhausts all possible symmetry protected line nodes in the presence of spin-orbit coupling and a (generalized) time-reversal symmetry. Implications for existing nonsymmorphic and antiferromagnetic superconductors are discussed.},
doi = {10.1103/PhysRevLett.118.207001},
journal = {Physical Review Letters},
number = 20,
volume = 118,
place = {United States},
year = {Thu May 18 00:00:00 EDT 2017},
month = {Thu May 18 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 5works
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