We investigate an optically trapped exciton-polariton condensate and observe temporal coherence beyond 1 ns in 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.

中文翻译：

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光学俘获激子-极化子凝聚中的超长时间相干性

我们研究了一种光学捕获的激子 - 极化子凝聚物，并观察了持续时间超过 1 ns 的时间相干性。由于与激子热库的空间重叠减少，被捕获的冷凝物的相干时间比未捕获的冷凝物的相干时间长一个数量级以上。这种超长相干性使捕获的凝聚物的高精度光谱成为可能，并且由于凝聚物的两种偏振模式的精细能量分裂，我们观察到场相关函数的周期性节拍。我们的结果对于在晶格势中实现具有自旋凝聚体的极化子模拟器很重要。