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arXiv · 2406.14674

Correlated and Critical Phenomena in Multipartite Quantum Non-Markovianity

Ignacio González·Ángel Rivas
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Abstract

We study non-Markovianity in the exact dynamics of two two-level atoms in a resonant cavity. We find a critical behavior in the form of a Markovian to non-Markovian transition at a finite interatomic distance and a discontinuity in the limit of infinitely close atoms. Actually, in this highly correlated regime, we find that non-Markovianity always arises if the system size exceeds a critical threshold. To this end, a non-singular, additive non-Markovian measure with appropriate asymptotic behavior is formulated. These results show how inter-subsystem distance and system size can act as precise controls for modulating memory effects in multipartite open quantum systems.

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Ignacio González, Ángel Rivas. 2024-06-20. Correlated and Critical Phenomena in Multipartite Quantum Non-Markovianity. https://doi.org/10.1103/physreva.111.l020204

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