Coherence Revivals and Lifetime Extension of Polariton Condensates by Mirror-Mediated Self-Feedback

TL;DR

This paper demonstrates that mirror-mediated self-feedback can control and extend the coherence of exciton-polariton condensates, showing coherence revivals and suppression of phase noise through delay tuning.

Contribution

The study introduces a novel feedback mechanism using time-delayed light reinjection to control coherence in polariton condensates, revealing new regimes of coherence revival and extension.

Findings

Long delays cause coherence revivals at multiples of the delay time.

Short delays suppress phase diffusion and nearly double coherence time.

A stochastic model explains coherence control via feedback and spectral filtering.

Abstract

Temporal coherence of driven-dissipative condensates is limited by phase noise. We show that mirror-mediated time-delayed self-feedback enables control of coherence in a trapped exciton-polariton condensate. Reinjecting a small fraction of the emitted light with a tunable delay reveals two regimes set by the ratio of delay time to intrinsic coherence time. Long delays result in pronounced coherence revivals at integer multiples of the feedback delay, while short delays suppress phase diffusion and nearly double the coherence time. A minimal stochastic delayed model reproduces both regimes and supports an interpretation in terms of phase stabilization and delay-induced spectral filtering.