Localization driven superradiant instability

TL;DR

This paper predicts a new type of superradiant instability driven by Anderson localization in a hybrid Dicke-Aubry-Andre model, revealing how localization can induce superradiance at minimal optical pumping levels.

Contribution

It introduces the concept of localization-driven superradiant instability in a hybrid system, contrasting with traditional superradiance in extended states, and connects it to current experimental setups.

Findings

Superradiant scattering is induced in localized bosons at near-zero pumping.

Localization causes superradiant instability independent of temperature.

The effect is distinct from superradiance in extended Bose condensates.

Abstract

The prominent Dicke superradiant phase arises from coupling an ensemble of atoms to cavity optical field when external optical pumping exceeds a threshold strength. Here we report a prediction of the superrandiant instability driven by Anderson localization, realized with a hybrid system of Dicke and Aubry-Andre (DAA) model for bosons trapped in a one-dimensional (1D) quasiperiodic optical lattice and coupled to a cavity. Our central finding is that for bosons condensed in localized phase given by the DAA model, the resonant superradiant scattering is induced, for which the critical optical pumping of superradiant phase transition approaches zero, giving an instability driven by Anderson localization. The superradiant phase for the DAA model with or without a mobility edge is investigated, showing that the localization driven superradiant instability is in sharp contrast to the superradiance as widely observed for Bose condensate in extended states, and should be insensitive to temperature of the system. This study unveils an insightful effect of localization on the Dicke superradiance, and is well accessible based on the current experiments.