Symmetry indicators for inversion-symmetric non-Hermitian topological band structures
File(s)PhysRevB.103.L201114.pdf (621.79 KB)
Published version
Author(s)
Vecsei, Pascal M
Denner, M Michael
Neupert, Titus
Schindler, Frank
Type
Journal Article
Abstract
We characterize non-Hermitian band structures by symmetry indicator topological invariants. Enabled by crystalline inversion symmetry, these indicators allow us to short-cut the calculation of conventional non-Hermitian topological invariants. In particular, we express the three-dimensional winding number of point-gapped non-Hermitian systems, which is defined as an integral over the whole Brillouin zone, in terms of symmetry eigenvalues at high-symmetry momenta. Furthermore, for time-reversal symmetric non-Hermitian topological insulators, we find that symmetry indicators characterize the associated Chern-Simons form, whose evaluation usually requires a computationally expensive choice of smooth gauge. In each case, we discuss the non-Hermitian surface states associated with nontrivial symmetry indicators.
Date Acceptance
2021-05-03
Citation
Physical Review B, 103 (20), pp.1-5
ISSN
2469-9950
Publisher
American Physical Society (APS)
Start Page
1
End Page
5
Journal / Book Title
Physical Review B
Volume
103
Issue
20
Copyright Statement
©2021 American Physical Society
Identifier
http://dx.doi.org/10.1103/physrevb.103.l201114
Publication Status
Published
Article Number
L201114
Date Publish Online
2021-05-21