Quantifying non-Markovianity via conditional mutual information

Zhiqiang Huang, Xiao-Kan Guo

Published 2021-03-02Version 1

In this paper, we study measures of quantum non-Markovianity based on the conditional mutual information. We obtain such measures by considering multiple parts of the total environment such that the conditional mutual informations can be defined in this multipartite setup. The benefit of this approach is that the conditional mutual information is closely related to recovery maps and Markov chains; we also point out its relations with the change of distinguishability. Moreover, we show how to extend the non-Markovianity measures to the case in which the initial system-environment state is correlated.