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arXiv · 2607.24406

Floquet time-convolutionless master equation for non-Markovian driven quantum systems

Pietro Follia·Heinz-Peter Breuer·Bassano Vacchini
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Abstract

We study the dynamics of open quantum systems driven by an external time-periodic force. Combining Floquet theory and the time-convolutionless projection operator technique we derive a time-local quantum master equation which exactly takes into account the periodic driving, while treating the system-environment interaction within second order in the coupling strength without performing the Markov approximation. The resulting equation of motion for the reduced density matrix is called Floquet time-convolutionless master equation. Employing the example of the driven spin-boson system, we demonstrate that this master equation is capable of describing strong non-Markovian effects, while yielding the Floquet-Lindblad master equation in the Markovian limit. A characteristic feature of memory effects in such driven dissipative systems is the emergence of sharp peaks of the trace-distance based non-Markovianity measure as a function of the driving amplitude, which can be traced back to quasienergy crossings leading to almost decoherence-protected subspaces through a quasienergy-induced dissipative decoupling mechanism.

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Pietro Follia, Heinz-Peter Breuer, Bassano Vacchini. 2026-07-27. Floquet time-convolutionless master equation for non-Markovian driven quantum systems. https://arxiv.org/abs/2607.24406

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