论文标题
观察连续的时间晶体
Observation of a continuous time crystal
论文作者
论文摘要
时间晶体根据它们是自发打破离散或连续的时间翻译对称性而分类为离散或连续的。自从他们最近发现以来，在定期驱动的系统中对离散的时间晶体进行了广泛的研究，但连续时间晶体的实验实现仍在待处理中。在这里，我们报告了连续泵送的耗散原子腔系统中极限周期阶段的观察，该系统的特征是腔内光子数中急剧振荡。我们观察到，对于不同的实现，这种振荡的相是随机的，因此这种动态的多体状态断裂了连续的时间翻译对称性。极限周期对时间扰动的观察到的鲁棒性证实了连续时间晶体的实现。
Time crystals are classified as discrete or continuous depending on whether they spontaneously break discrete or continuous time translation symmetry. While discrete time crystals have been extensively studied in periodically driven systems since their recent discovery, the experimental realization of a continuous time crystal is still pending. Here, we report the observation of a limit cycle phase in a continuously pumped dissipative atom-cavity system, which is characterized by emergent oscillations in the intracavity photon number. We observe that the phase of this oscillation is random for different realizations, and hence this dynamical many-body state breaks continuous time translation symmetry spontaneously. The observed robustness of the limit cycles against temporal perturbations confirms the realization of a continuous time crystal.
