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arXiv · 2010.14829

Variational principle for time-periodic quantum systems

Nils Krüger
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Abstract

A variational principle enabling one to compute individual Floquet states of a periodically time-dependent quantum system is formulated, and successfully tested against the benchmark system provided by the analytically solvable model of a linearly driven harmonic oscillator. The principle is particularly well suited for tracing individual Floquet states through parameter space, and may allow one to obtain Floquet states even for very high-dimensional systems which cannot be treated by the known standard numerical methods.

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Nils Krüger. 2020-10-28. Variational principle for time-periodic quantum systems. https://doi.org/10.1515/zna-2020-0209

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