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arXiv · 2012.08217

Photonic Floquet time crystals

Bing Wang·Jiaqi Quan·Jianfei Han·Xiaopeng Shen·Hongwei Wu·Yiming Pan
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Abstract

The public and scientists constantly have different perspectives. While on a time crystal, they stand in line and ask: What is a time crystal? Show me a material that is spontaneously crystalline in time? This study synthesizes a photonic material of Floquet time crystals and experimentally observes its indicative period-2T beating. We explicitly reconstruct a discrete time-crystalline ground state and reveal using an appropriately-designed photonic Floquet simulator the rigid period-doubling as a signature of the spontaneous breakage of the discrete time-translational symmetry. Unlike the result of the exquisite many-body interaction, the photonic time crystal is derived from a single-particle topological phase that can be extensively accessed by many pertinent nonequilibrium and periodically-driven platforms. Our observation will drive theoretical and technological interests toward condensed matter physics and topological photonics, and demystify time crystals for the non-scientific public.

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BibTeXRIS

Bing Wang, Jiaqi Quan, Jianfei Han, Xiaopeng Shen, Hongwei Wu, Yiming Pan. 2020-12-15. Photonic Floquet time crystals. https://doi.org/10.1002/lpor.202100469

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