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arXiv · 2302.08395

Quantum work statistics at strong reservoir coupling

Owen Diba·Harry J. D. Miller·Jake Iles-Smith·Ahsan Nazir
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Abstract

Determining the statistics of work done on a quantum system while strongly coupled to a reservoir is a formidable task, requiring the calculation of the full eigenspectrum of the combined system and reservoir. Here we show that this issue can be circumvented by using a polaron transformation that maps the system into a new frame where weak-coupling theory can be applied. Crucially, this polaron approach reproduces the Jarzynski fluctuation theorem, thus ensuring consistency with the laws of stochastic thermodynamics. We apply our formalism to a system driven across the Landau-Zener transition, where we identify clear signatures in the work distribution arising from a non-negligible coupling to the environment. Our results provide a new method for studying the stochastic thermodynamics of driven quantum systems beyond Markovian, weak-coupling regimes.

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Owen Diba, Harry J. D. Miller, Jake Iles-Smith, Ahsan Nazir. 2023-02-16. Quantum work statistics at strong reservoir coupling. https://doi.org/10.1103/physrevlett.132.190401

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