Perspective on topological states of non-Hermitian lattices

Luis E F Foa Torres

Journal of Physics: Materials 3, 014002 (2020)

doi:10.1088/2515-7639/ab4092

Free access article

Abstract

The search of topological states in non-Hermitian systems has gained a strong momentum over the last two years climbing to the level of an emergent research front. In this perspective we give an overview with a focus on connecting this topic to others like Floquet systems. Furthermore, using a simple scattering picture we discuss an interpretation of concepts like the Hamiltonian’s defectiveness, i.e. the lack of a full basis of eigenstates, crucial in many discussions of topological phases of non-Hermitian Hamiltonians.

Note: Invited article for Focus Issue on Topological Matter