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arXiv · 2511.04339

Synchronization effects in a periodically driven two-level system

Federico Settimo·Bassano Vacchini
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Abstract

We study phase-synchronization in a driven two-level system coupled to a non-Markovian bosonic reservoir. The dynamics is described by treating the system-bath coupling and the coherent drive without invoking the rotating-wave approximation, and simulated using the numerically exact hierarchical equations of motion. We observe that a robust phase-locking develops and that the corresponding synchronization measure rapidly acquires a finite value when the system is tuned to what we identify as a resonant-ratio condition, namely when the ratio between the drive amplitude and its frequency coincides with a zero of the Bessel function $J_0$. We provide an explanation for this phenomenon by means of a static approximation derived from a Fourier analysis of the periodically driven Hamiltonian.

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Federico Settimo, Bassano Vacchini. 2025-11-06. Synchronization effects in a periodically driven two-level system. https://doi.org/10.1103/cswq-l3c8

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