2019年3月
Symmetry-protected exceptional rings in two-dimensional correlated systems with chiral symmetry
Physical Review B(Rapid Communication)
- ,
- ,
- ,
- 巻
- 99
- 号
- 12
- 開始ページ
- 121101
- 終了ページ
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1103/PhysRevB.99.121101
- 出版者・発行元
- AMER PHYSICAL SOC
Emergence of exceptional points in two dimensions is one of the remarkable phenomena in non-Hermitian systems. We here elucidate the impacts of symmetry on the non-Hermitian physics. Specifically, we analyze chiral symmetric correlated systems in equilibrium where the non-Hermitian phenomena are induced by the finite lifetime of quasiparticles. Intriguingly, our analysis reveals that the combination of symmetry and non-Hermiticity results in topological degeneracies of energy bands which we call symmetry-protected exceptional rings (SPERs). We observe the emergence of SPERs by analyzing a non-Hermitian Dirac Hamiltonian. Furthermore, by employing the dynamical mean-field theory, we demonstrate the emergence of SPERs in a correlated honeycomb lattice model whose single-particle spectrum is described by a non-Hermitian Dirac Hamiltonian. We uncover that the SPERs survive even beyond the non-Hermitian Dirac Hamiltonian, which is related to a zeroth Chern number. The argument of symmetry protection also holds for three dimensions, elucidating the presence of a symmetry-protected exceptional torus.
- リンク情報
- ID情報
-
- DOI : 10.1103/PhysRevB.99.121101
- ISSN : 2469-9950
- eISSN : 2469-9969
- Web of Science ID : WOS:000460723200001