Dynamics of long-range order in an exciton-polariton condensate

TL;DR

This study investigates the development and decay of spatial coherence in an exciton-polariton condensate, revealing rapid onset at stimulated scattering and prolonged coherence decay, supported by a stochastic classical field model.

Contribution

It provides the first time-resolved measurements of spatial coherence dynamics in exciton-polariton condensates and models these behaviors considering disorder and reservoir interactions.

Findings

Long-range coherence appears at stimulated scattering onset.

Coherence peaks and then decays over hundreds of picoseconds.

Model qualitatively reproduces experimental coherence dynamics.

Abstract

We report on time resolved measurements of the first order spatial coherence in an exciton polariton Bose-Einstein condensate. Long range spatial coherence is found to set in right at the onset of stimulated scattering, on a picosecond time scale. The coherence reaches its maximum value after the population and decays slower, staying up to a few hundreds of picoseconds. This behavior can be qualitatively reproduced, using a stochastic classical field model describing interaction between the polariton condensate and the exciton reservoir within a disordered potential.