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arXiv · 2503.18465

Degree of simplicity of Floquet states of a periodically driven Bose-Hubbard dimer

Steffen Seligmann·Martin Holthaus
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Abstract

We investigate numerically computed Floquet states of a Bose-Hubbard dimer which is subjected to strong, time-periodic forcing with respect to their coherence, invoking a measure for their degree of simplicity previously suggested by Leggett. This serves to ascertain the validity of the mean-field approximation under conditions such that the time-dependent nonlinear Gross-Pitaevskii equation has chaotic solutions. It is shown that for sufficiently large particle numbers the exact N-particle Floquet state semiclassically associated with the innermost quantized invariant tube surrounding a stable periodic mean-field orbit represents a macroscopically occupied single-particle state, i.e., a Floquet condensate.

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Steffen Seligmann, Martin Holthaus. 2025-03-24. Degree of simplicity of Floquet states of a periodically driven Bose-Hubbard dimer. https://doi.org/10.1103/nqg9-788r

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