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arXiv · 1805.00920

A correlation measure detecting almost all non-Markovian evolutions

Dario De Santis·Markus Johansson·Bogna Bylicka·Nadja K. Bernardes·Antonio Acín
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Abstract

We investigate the ability of correlation measures to witness non-Markovian open quantum system dynamics. It is shown that the mutual information and any entanglement measure between the system and an ancilla do not witness all non-Markovian dynamics. A correlation measure is introduced, and it is proven that, in an enlarged setting with two ancillary systems, this measure detects almost all non-Markovian dynamics, except possibly a zero-measure set of dynamics that is non-bijective in finite time-intervals. Our proof is constructive and provides different initial states detecting the non-Markovian evolutions. These states are all separable and some are arbitrarily close to a product state.

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Dario De Santis, Markus Johansson, Bogna Bylicka, Nadja K. Bernardes, Antonio Acín. 2018-05-02. A correlation measure detecting almost all non-Markovian evolutions. https://doi.org/10.1103/physreva.99.012303

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