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arXiv · 2504.00578

Pre-Floquet states facilitating coherent subharmonic response of periodically driven many-body systems

Steffen Seligmann·Hamed Koochaki Kelardeh·Martin Holthaus
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Abstract

We demonstrate longtime coherent subharmonic motion of a many-boson system subjected to an external time-periodic driving force. The underlying mechanism is exemplified numerically through analysis of a periodically driven Bose-Hubbard dimer, and clarified conceptually by semiclassical requantization of invariant tubes pertaining to the system's mean-field description. In this way, one arrives at pre-Floquet states that relate to the actual many-body Floquet states in a manner similar to the relation of site-localized Wannier states to lattice-extended Bloch states in solid-state physics. It is argued that even high-order subharmonic response can be systematically engineered, and be observed experimentally, with weakly interacting Floquet condensates comprising a sufficiently large number of particles.

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Steffen Seligmann, Hamed Koochaki Kelardeh, Martin Holthaus. 2025-04-01. Pre-Floquet states facilitating coherent subharmonic response of periodically driven many-body systems. https://doi.org/10.1103/vgpm-s6tv

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