Non-Hermitian Edge Burst

TL;DR

This paper discovers a novel non-Hermitian phenomenon called edge burst, where significant loss occurs at the boundary of certain quantum systems due to unique non-Hermitian effects, with universal scaling relations and experimental relevance.

Contribution

It introduces the concept of edge burst in non-Hermitian quantum dynamics, linking it to the interplay of skin effect and imaginary gap closing, and establishes a universal bulk-edge scaling relation.

Findings

Large boundary loss observed in non-Hermitian quantum walks.

Edge burst explained by skin effect and imaginary gap closing.

Universal bulk-edge scaling relation established.

Abstract

We unveil an unexpected non-Hermitian phenomenon, dubbed edge burst, in non-Hermitian quantum dynamics. Specifically, in a class of non-Hermitian quantum walk in periodic lattices with open boundary condition, an exceptionally large portion of loss occurs at the system boundary. The physical origin of this edge burst is found to be an interplay between two unique non-Hermitian phenomena: non-Hermitian skin effect and imaginary gap closing. Furthermore, we establish a universal bulk-edge scaling relation underlying the non-Hermitian edge burst. Our predictions are experimentally accessible in various non-Hermitian systems including quantum-optical and cold-atom platforms.