Quantum dynamical signatures of non-Hermitian boundary modes

Abstract

The non-Hermitian bulk-boundary correspondence features an interplay between the non-Hermitian skin effect and anomalous boundary-mode behavior. Whereas the skin effect is known to manifest itself in quantum dynamics in the form of chiral damping, it has remained less clear what impact the boundary modes may have. Here we derive experimentally accessible signatures of the boundary modes. We also establish clear criteria, based on the generalized Brillouin zone, that determine when bulk and boundary effects can be dynamically discerned using the Liouvillian separation gap. This leads to telltale signatures in both stable regimes -- where particle number remains finite -- and in the unstable regimes -- where a macroscopic boundary mode population occurs.