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arXiv · 2202.13761

Global Correlation and Local Information Flows in Controllable Non-Markovian Open Quantum Dynamics

Xin-Yu Chen·Na-Na Zhang·Wan-Ting He·Xiang-Yu Kong·Ming-Jie Tao·Fu-Guo Deng·Qing Ai·Gui-Lu Long
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Abstract

In a fully-controllable experiment platform for studying non-Markovian open quantum dynamics, we show that the non-Markovianity could be investigated from the global and local aspects. By mixing random unitary dynamics, we demonstrate non-Markovian and Markovian open quantum dynamics. From the global point of view, by tuning the base frequency we demonstrate the transition from the Markovianity to the non-Markovianity as measured by the quantum mutual information (QMI). In a Markovian open quantum process, the QMI decays monotonically, while it may rise temporarily in a non-Markovian process. However, under some circumstances, it is not sufficient to globally investigate the non-Markovianity of the open quantum dynamics. As an essential supplement, we further utilize the quantum Fisher information (QFI) flow to locally characterize the non-Markovianity in different channels. We demonstrate that the QMI in combination with the QFI flow are capable of measuring the non-Markovianity for a multi-channel open quantum dynamics.

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Xin-Yu Chen, Na-Na Zhang, Wan-Ting He, Xiang-Yu Kong, Ming-Jie Tao, Fu-Guo Deng, Qing Ai, Gui-Lu Long. 2022-02-28. Global Correlation and Local Information Flows in Controllable Non-Markovian Open Quantum Dynamics. https://doi.org/10.1038/s41534-022-00537-z

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