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arXiv · 1202.4280

System-environment correlations and Non-Markovian dynamics

Ansgar Pernice·Julius Helm·Walter T. Strunz
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Abstract

We determine the total state dynamics of a dephasing open quantum system using the standard environment of harmonic oscillators. Of particular interest are random unitary approaches to the same reduced dynamics and system-environment correlations in the full model. Concentrating on a model with an at times negative dephasing rate, the issue of "non-Markovianity" will also be addressed. Crucially, given the quantum environment, the appearance of non-Markovian dynamics turns out to be accompanied by a loss of system-environment correlations. Depending on the initial purity of the qubit state, these system-environment correlations may be purely classical over the whole relevant time scale, or there may be intervals of genuine system-environment entanglement. In the latter case, we see no obvious relation between the build-up or decay of these quantum correlations and "Non-Markovianity".

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Ansgar Pernice, Julius Helm, Walter T. Strunz. 2012-02-20. System-environment correlations and Non-Markovian dynamics. https://doi.org/10.1088/0953-4075/45/15/154005

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