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arXiv · 2202.11056

Quantum regression in dephasing phenomena

Davide Lonigro·Dariusz Chruściński
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Abstract

We investigate the validity of quantum regression for a family of quantum Hamiltonians on a multipartite system leading to phase-damping reduced dynamics. After finding necessary and sufficient conditions for the CP-divisibility of the corresponding channel, we evaluate a hierarchy of equations equivalent to the validity of quantum regression under arbitrary interventions; in particular, we find necessary conditions for a nontrivial dephasing to be compatible with quantum regression. In this framework, we study a class of dephasing-type generalized spin-boson (GSB) models, investigating the existence of qubit-environment coupling functions that ensure the exact validity of quantum regression.

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Davide Lonigro, Dariusz Chruściński. 2022-02-22. Quantum regression in dephasing phenomena. https://doi.org/10.1088/1751-8121%2Fac6a2d

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