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arXiv · 2201.12326

Quantum regression beyond the Born-Markov approximation for generalized spin-boson models

Davide Lonigro·Dariusz Chruściński
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Abstract

The quantum regression formula for an open quantum system consists in an infinite hierarchy of conditions for its multi-time correlation functions, thus requiring full access to the total "system+environment" evolution, and providing a stronger requirement than CP-divisibility. Here, we analyze CP-divisibility and check the validity of quantum regression beyond the Born-Markov approximation (e.g. weak coupling limit) for a class of generalized spin-boson (GSB) models giving rise to a multi-level amplitude-damping evolution; in all cases, it is possible to engineer the system-bath coupling in such a way that quantum regression is exactly satisfied.

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Davide Lonigro, Dariusz Chruściński. 2022-01-28. Quantum regression beyond the Born-Markov approximation for generalized spin-boson models. https://doi.org/10.1103/physreva.105.052435

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