Physical Review A

Exact non-Markovian dynamics of qubits coupled to two interacting environments

H. Z. Shen, Dongxiao Li, Shi‐Lei Su, Y. H. Zhou, X. X. Yi

Published Sep 5, 2017• 31 citations

Abstract

As the memory effect may be helpful in quantum information processing, non-Markovian dynamics plays an important role in the description of many-body open systems. Among these topics, the system consisting of independent qubits interacting with several coupled environments is of particular interest. In this paper, we study the exact non-Markovian dynamics of two independent qubits. Each of the qubits interacts individually with its environment, and these two environments coupled with each other. We investigate the non-Markovianity measure of the system for the whole parameter regime without the rotating-wave approximation (RWA) and compare the results with that under the RWA. We find that the non-Markovianity measure for two qubits manifests a transition from a non-Markovian to Markovian regime regardless of the coupling strength between the environments. The physical origin of this transition is revealed, and a possible observation of the prediction in superconducting quantum interference devices is discussed.

DOI: 10.1103/physreva.96.033805

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