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arXiv · 1611.01483

Refined Weak Coupling Limit: Coherence, Entanglement and Non-Markovianity

Ángel Rivas
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Abstract

We study the properties of a refined weak coupling limit that preserves complete positivity in order to describe non-Markovian dynamics in the spin-boson model. With this tool, we show the system presents a rich and new non-Markovian phenomenology. This implies a dynamical difference between entanglement and coherence: the latter undergoes revivals whereas the former not, despite the induced dynamics being fully incoherent. In addition, the evolution presents "quasieternal" non-Markovianity, becoming non-divisible at any time period where the system evolves qualitatively. Furthermore, the method allows for an exact derivation of a master equation that accounts for a reversible energy exchange between system and environment. Specifically, this is obtained in the form of a time-dependent Lamb shift term.

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Ángel Rivas. 2017-04-07. Refined Weak Coupling Limit: Coherence, Entanglement and Non-Markovianity. https://doi.org/10.1103/physreva.95.042104

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