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arXiv · 2111.12998

Following Floquet states in high-dimensional Hilbert spaces

Abstract

An iterative algorithm is established which enables one to compute individual Floquet states even for many-body systems with high-dimensional Hilbert spaces that are not accessible to commonly employed conventional methods. A strategy is proposed for following a Floquet state in response to small changes of a given system's Hamiltonian. The scheme is applied to a periodically driven Bose-Hubbard chain, verifying the possibility of pseudoadiabatic Floquet state following. In particular, it is demonstrated that a driving-induced Mott insulatorlike target Floquet state can be populated with high efficiency if the driving amplitude is turned on smoothly but not too slowly. We conclude that the algorithm constitutes a powerful tool for the future investigation of many-body Floquet systems.

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Nils Krüger, Martin Holthaus. 2021-11-25. Following Floquet states in high-dimensional Hilbert spaces. https://doi.org/10.1103/physrevresearch.3.043133

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