From Dicke to Anderson: Interplay of Superradiance and Disorder

TL;DR

This paper investigates how disorder and superradiance interact in open quantum systems modeled by Anderson models, revealing a transition to superradiance and differing sensitivities of eigenstates to disorder.

Contribution

It introduces a non-Hermitian Hamiltonian approach to analyze the interplay of disorder and superradiance in Anderson models across different dimensions.

Findings

Superradiant regime transition identified via complex eigenvalues.

Superradiant states remain delocalized with increasing disorder.

Subradiant states are highly sensitive to disorder.

Abstract

Using a non-Hermitian Hamiltonian approach to open systems, we study the interplay of disorder and superradiance in a one- and three-dimensional Anderson model. Analyzing the complex eigenvalues of the non-Hermitian Hamiltonian, a transition to a superradiant regime is shown to occur. As an effect of openness the structure of eigenstates undergoes a strong change in the superradiant regime: we show that the sensitivity to disorder of the superradiant and the subradiant subspaces is very different; superradiant states remain delocalized as disorder increases, while subradiant states are sensitive to the degree of disorder.