Mode-locking and mode-competition in a non-equilibrium solid-state condensate

TL;DR

This paper investigates the behavior of a non-equilibrium polariton condensate under continuous pumping and decay, revealing complex steady-states including mode-locking and competition, with results aligning with experimental observations.

Contribution

It introduces a generalized Gross-Pitaevskii model to analyze non-equilibrium condensates, highlighting novel mode-locking and competition phenomena not seen in equilibrium systems.

Findings

Identification of various steady-states with multiple populated modes

Observation of synchronization transition at a critical density

Consistency of critical density estimates with experimental data

Abstract

A trapped polariton condensate with continuous pumping and decay is analyzed using a generalized Gross-Pitaevskii model. Whereas an equilibrium condensate is characterized by a macroscopic occupation of a ground state, here the steady-states take more general forms. Some are characterized by a large population in an excited state, and others by large populations in several states. In the latter case, the highly-populated states synchronize to a common frequency above a critical density. Estimates for the critical density of this synchronization transition are consistent with experiments.