Ultralong temporal coherence in optically trapped exciton-polariton condensates

TL;DR

This study demonstrates ultralong temporal coherence in optically trapped exciton-polariton condensates, significantly surpassing untrapped counterparts, enabling high-precision spectroscopy and potential applications in polariton-based quantum simulators.

Contribution

It reveals that optical trapping extends the coherence time of exciton-polariton condensates by reducing thermal reservoir overlap, a novel approach for enhancing coherence in these systems.

Findings

Coherence time exceeds 1 nanosecond in trapped condensates.

Observation of periodic beats in the field correlation function.

Reduced thermal reservoir overlap leads to longer coherence.

Abstract

We investigate an optically trapped exciton-polariton condensate and observe temporal coherence beyond 1~ns duration. Due to the reduction of the spatial overlap with the thermal reservoir of excitons, the coherence time of the trapped condensate is more than an order of magnitude longer than that of an untrapped condensate. This ultralong coherence enables high precision spectroscopy of the trapped condensate, and we observe periodic beats of the field correlation function due to a fine energy splitting of two polarization modes of the condensate. Our results are important for realizing polariton simulators with spinor condensates in lattice potentials.