Non-Hermitian $C_{NH}=2$ Chern insulator protected by generalized rotational symmetry

Abstract

We propose a non-Hermitian topological system protected by the generalized rotational symmetry which invokes rotation in space and Hermitian conjugation. The system, described by the tight-binding model with nonreciprocal hopping, is found to host two pairs of in-gap edge modes in the gapped topological phase and is characterized by the non-Hermitian (NH) Chern number $C_{NH}=2$. The quantization of the non-Hermitian Chern number is shown to be protected by the generalized rotational symmetry ${\hat{H}}^{+}=\hat{U}\hat{H}{\hat{U}}^{+}$ of the system. Our finding paves the way towards novel non-Hermitian topological systems characterized by large values of topological invariants and hosting multiple in-gap edge states, which can be used for topologically resilient multiplexing.

arXiv comment8 pages, 3 figures

References in corpus (33)

• Topological Insulators
• Topological insulators and superconductors
• Real Spectra in Non-Hermitian Hamiltonians Having PT Symmetry
• Topological Photonics
• Topological Photonics
• Classification of topological insulators and superconductors in three spatial dimensions
• Classification of topological quantum matter with symmetries
• Novel Symmetry Classes in Mesoscopic Normal-Superconducting Hybrid Structures
• Edge states and topological invariants of non-Hermitian systems
• Topological Crystalline Insulators
• Non-Hermitian Physics
• Topological phases of non-Hermitian systems
• Symmetry and Topology in Non-Hermitian Physics
• Biorthogonal Bulk-Boundary Correspondence in Non-Hermitian Systems
• Topological Band Theory for Non-Hermitian Hamiltonians
• Non-Hermitian Chern bands
• Observation of bulk boundary correspondence breakdown in topolectrical circuits
• Observation of non-Hermitian bulk-boundary correspondence in quantum dynamics
• Non-Hermitian skin effect and chiral damping in open quantum systems
• Non-Hermitian bulk-boundary correspondence and auxiliary generalized Brillouin zone theory
• Non-Hermitian Topological Invariants in Real Space
• Critical non-Hermitian Skin Effect
• Observation of arbitrary topological windings of a non-Hermitian band
• Non-Hermitian skin modes induced by on-site dissipations and chiral tunneling effect
• Topological Classification of Non-Hermitian Hamiltonians
• Topological non-Hermitian origin of surface Maxwell waves
• Topological classification of non-Hermitian systems with reflection symmetry
• Exceptional points in topological edge spectrum of PT symmetric domain walls
• Bulk-edge correspondence for Chern topological phases: A viewpoint from a generalized index theorem
• Topological phases and nonreciprocal edge states in non-Hermitian Floquet Insulators
• Inversion symmetric non-Hermitian Chern insulator
• Exceptional points make an astroid in non-Hermitian Lieb lattice: evolution and topological protection
• Generating and detecting topological phases with higher Chern number

Cited by in corpus (5)

• Edge State, Band Topology, and Time Boundary Effect in the Fine-Grained Categorization of Chern Insulators
• Extension of Noether's theorem in PT-symmetric systems and its experimental demonstration in an optical setup
• Probing Bulk Band Topology from Time Boundary Effect in Synthetic Dimension
• Discriminant indicator with generalized rotational symmetry
• Hybrid Higher-Order Skin Topological Modes in the Two-Dimensional Su-Schrieffer-Heeger Model with Nonreciprocal Hoppings