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 information 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 in distinguishability. We study along the way the properties of leaked information, which is the conditional mutual information that can be back flowed, and we use this leaked information to show that the correlated environment is necessary for the nonlocal memory effect.

中文翻译：

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通过条件互信息量化非马尔可夫性

在本文中，我们研究了基于条件互信息的量子非马尔可夫度量。我们通过考虑整个环境的多个部分来获得此类度量，以便可以在此多部分设置中定义条件互信息。这种方法的好处是条件互信息与恢复图和马尔可夫链密切相关；我们还指出了它与可区分性变化的关系。我们沿途研究了泄漏信息的性质，即可以回流的条件互信息，我们使用这些泄漏信息表明相关环境对于非局部记忆效应是必要的。