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arXiv · 2411.00651

Nonperturbative decay of bipartite discrete time crystals

Lennart Fernandes·Joseph Tindall·Dries Sels
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Abstract

We study prethermal time-crystalline order in periodically driven quantum Ising models on disorder-free decorated lattices. Using a tensor network ansatz for the state which reflects the geometry of a unit cell of the lattice, we show through finite entanglement scaling that the system has an exponentially long-lived subharmonic response in the thermodynamic limit, which decays nonperturbatively in deviations from a perfect periodic drive. The resulting prethermal discrete time crystal is not only stable to imperfections in the transverse field, but also exhibits a bipartite rigidity to generic perturbations in the longitudinal field. We call this state a bipartite discrete time crystal and reveal a rich prethermal phase diagram, including multiple regions of bipartite time-crystalline order, uniform time-crystalline order and thermalization, with boundaries depending delicately on the topology of the decorated lattice. Our results thus uncover a variety of time crystals which may be realized on current digital quantum processors and analog quantum simulators.

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Lennart Fernandes, Joseph Tindall, Dries Sels. 2024-11-01. Nonperturbative decay of bipartite discrete time crystals. https://doi.org/10.1103/physrevb.111.l100304

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