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arXiv · 2312.17070

Swapping Floquet time crystal

Roberto Gargiulo·Gianluca Passarelli·Procolo Lucignano·Angelo Russomanno
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Abstract

We propose a Floquet period-doubling time-crystal model based on a disordered interacting long-range spin chain where the periodic swapping of nearby spin couples is applied. This protocol can be applied to systems with any local spin magnitude $s$ {and in principle also to systems with nonspin (fermionic or bosonic) local Hilbert space}. We explicitly consider the cases $s = 1/2$ and $s = 1$, using analytical and numerical methods to show that the time-crystal behavior appears in a range of parameters. In particular, we study the persistence of period-doubling oscillations in time, the time-crystal properties of the Floquet spectrum (quasienergy $\pi$-spectral pairing and long-range correlations of the Floquet states), and introduce a quantity (the local imbalance) to assess what initial states give rise to a period-doubling dynamics. We also consider the average level spacing ratio and find that the interval of parameters where the system does not thermalize and persistent period-doubling is possible corresponds to the one where the Floquet spectrum shows time-crystal properties.

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Roberto Gargiulo, Gianluca Passarelli, Procolo Lucignano, Angelo Russomanno. 2023-12-28. Swapping Floquet time crystal. https://doi.org/10.1103/physrevb.109.174310

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