Photonic Floquet time crystals

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.

39 pages, 5 figures, supplementary materials, 6 suppl. figures

References in corpus (3)

• Absence of Quantum Time Crystals
• Discrete Time-Crystalline Order in Cavity and Circuit QED Systems
• Floquet engineering of long-range p-wave superconductivity

Cited by in corpus (11)

• Photonic Metamaterial Analogue of a Continuous Time Crystal
• Quasiperiodic disorder induced critical phases in a periodically driven dimerized $p$-wave Kitaev chain
• Dynamical Detection of Topological Spectral Density
• Topological properties of a periodically driven Creutz ladder
• Topologically protected boundary discrete time crystal for a solvable model
• Topological $\pi$ modes and beyond
• Topological characterization of a non-Hermitian ladder via Floquet non-Bloch theory
• Single and multi-frequency driving protocols in a Rashba nanowire proximitized to an s-wave superconductor
• A Solvable Model for Discrete Time Crystal Enforced by Nonsymmorphic Dynamical Symmetry
• Floquet Non-Bloch Formalism for a Non-Hermitian Ladder: From Theoretical Framework to Topolectrical Circuits
• $q$th-root non-Hermitian Floquet topological insulators