First-order dissipative phase transition in an exciton-polariton condensate

TL;DR

This paper explores the phase diagram of a driven-dissipative exciton-polariton system, revealing two critical points: one for quasi-condensation and another for a first-order transition to a uniform state, with signatures of BKT-like behavior.

Contribution

It uncovers the existence of a first-order phase transition and a BKT-like transition in a 2D polariton system, providing new insights into its phase behavior.

Findings

Identification of two critical points in the phase diagram.

Evidence of a first-order phase transition with density discontinuity.

Observation of BKT-like transition signatures in the non-uniform phase.

Abstract

We investigate the phase diagram of a two-dimensional driven-dissipative system of polaritons coupled to the excitonic reservoir. We find that two critical points exists. The first corresponds to the quasi-condensation and the second to a first-order phase transition from the non-uniform state with spatially modulated density to a uniform state. The latter is related to the modulational instability of a homogeneous state due to the repulsive interactions with the non-condensed reservoir. The first-order character of the transition is evidenced by a discontinuity in the density and the correlation length as well as the phase coexistence and metastability. Moreover, we show that a signature of a Berezinskii-Kosterlitz-Thouless-like transition can be observed in the non-uniform phase.