Universal Hall conductance scaling in non-Hermitian Chern insulators

TL;DR

This paper reveals a universal power-law scaling in the Hall conductance of non-Hermitian Chern insulators, showing how gain and loss induce non-analytical behavior near phase transitions, with implications for electronic transport.

Contribution

It introduces a biorthogonal linear response theory to analyze Hall conductance in non-Hermitian systems, uncovering universal 3/2 power-law scaling near critical points.

Findings

Universal 3/2 power-law scaling of Hall conductance near phase transition

Non-analytical contributions induced by gain and loss

Potential for experimental observation of non-Hermitian topological effects

Abstract

We investigate the Hall conductance of a two-dimensional Chern insulator coupled to an environment causing gain and loss. Introducing a biorthogonal linear response theory, we show that sufficiently strong gain and loss lead to a characteristic non-analytical contribution to the Hall conductance. Near its onset, this contribution exhibits a universal power-law with a power 3/2 as a function of Dirac mass, chemical potential and gain strength. Our results pave the way for the study of non-Hermitian topology in electronic transport experiments.