Topological exceptional surfaces in non-Hermitian systems with parity-time and parity-particle-hole symmetries

2018/10/31 by Ryo Okugawa, Takehito Yokoyama · 3 citations
Mathematics · Physics and Astronomy · #Combinatorics #Geometry #Hermitian matrix #Homogeneous space #Mathematics #Noncommutative and Quantum Gravity Theories #Parity (physics) #Physics #Quantum Mechanics and Non-Hermitian Physics #Quantum mechanics #Theoretical physics #Topological Materials and Phenomena #Topology (electrical circuits) #cond-mat.mes-hall #cond-mat.supr-con #physics.optics

paper · pdf · doi:10.1103/physrevb.99.041202

published as Phys. Rev. B 99, 041202 (2019) · 7 pages, 3 figures. Figures improved

arxiv created 2019/01/24 · openalex publication_date 2019/01/24 · arxiv updated 2019/01/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Non-Hermiticity makes possible novel topological phenomena, which are notallowed in Hermitian systems. The authors show that topologically nontrivial band degeneracies can appear as exceptional surfaces in non-Hermitian systems with parity--time and parity--particle-hole symmetries. It is shown that when parity--time or parity--particle-hole symmetry is present, d-dimensional non-Hermitian systems can have (d\ensuremath-1)-dimensional exceptional surfaces. This work suggests new topological phases with nodal band structures protected by non-Hermitian topology and symmetry.

Citations

• Four-Dimensional Quantum Hall Effect with Ultracold Atoms
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• Physics of Nonhermitian Degeneracies
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Cited by

• Equilibrium Thermodynamics of Non-Hermitian Dirac Fermions: Caloric and Magnetic Responses
• Spectrum Collapse of Disordered Dirac Landau Levels as Topological Non-Hermitian Physics
• Hopf Exceptional Points
• Non-Bloch band theory and bulk–edge correspondence in non-Hermitian systems