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arXiv · 2303.03615

Assessing non-Markovian dynamics through moments of the Choi state

Bivas Mallick·Saheli Mukherjee·Ananda G. Maity·A. S. Majumdar
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Abstract

Non-Markovian effects in open quantum system dynamics usually manifest backflow of information from the environment to the system, indicating complete-positive divisibility breaking of the dynamics. We provide a criterion for witnessing such non-Markovian dynamics exhibiting information backflow, based on the moments of Choi-matrices. The moment condition determined by the positive semi-definiteness of a matrix, does not hold for a Choi-state describing non-Markovian dynamics. We then present some explicit examples in support of our proposed non-Markovianity detection scheme. Finally, a moment based measure of non-Markovianity for unital dynamics is formulated.

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Bivas Mallick, Saheli Mukherjee, Ananda G. Maity, A. S. Majumdar. 2023-03-07. Assessing non-Markovian dynamics through moments of the Choi state. https://doi.org/10.1103/physreva.109.022247

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