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arXiv · 1404.5280

Crossover Between Non-Markovian and Markovian Dynamics Induced by a Hierarchical Environment

Tiantian Ma·Yusui Chen·Tian Chen·Samuel R. Hedemann·Ting Yu
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Abstract

Non-Markovian evolution of an open quantum system can be induced by the memory effects of a reservoir. Although a reservoir with stronger memory effects may seem like it should cause stronger non-Markovian effects on the system of interest, this seemingly intuitive thinking may not always be correct. We illustrate this by investigating a qubit (a two-level atom) that is coupled to a hierarchical environment, which contains a single-mode cavity and a reservoir consisting of infinite numbers of modes. We show how the non-Markovian character of the system is influenced by the coupling strength between the qubit and cavity and the correlation time of the reservoir. In particular, we found a new phenomenon whereby the qubit Markovian and non-Markovian transition exhibits a anomalous pattern in a parameter space depicted by the coupling strength and the correlation time of the reservoir.

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Tiantian Ma, Yusui Chen, Tian Chen, Samuel R. Hedemann, Ting Yu. 2014-10-10. Crossover Between Non-Markovian and Markovian Dynamics Induced by a Hierarchical Environment. https://doi.org/10.1103/physreva.90.042108

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