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arXiv · 2309.05641

Long-time properties of generic Floquet systems are approximately periodic with the driving period

Yichen Huang
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Abstract

A Floquet quantum system is governed by a Hamiltonian that is periodic in time. Consider the space of piecewise time-independent Floquet systems with (geometrically) local interactions. We prove that for all but a measure zero set of systems in this space, starting from a random product state, many properties (including expectation values of observables and the entanglement entropy of a macroscopically large subsystem) at long times are approximately periodic with the same period as the Hamiltonian. Thus, in almost every Floquet system of arbitrarily large but finite size, discrete time-crystalline behavior does not persist to strictly infinite time.

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Yichen Huang. 2023-09-11. Long-time properties of generic Floquet systems are approximately periodic with the driving period. https://doi.org/10.1088/1367-2630/ad5eb1

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