International Journal of Modern Physics B

Dynamics of measurement-induced nonlocality of quantum states in a structured environment

XIAO SAN MA, Mu-Tian Cheng, Qiao Ying

Published Oct 14, 2016• 2 citations

Abstract

In this paper, we analyze the dynamics of the measurement-induced nonlocality (MIN) of two-qubit states undergoing decoherence induced by a structured environment modeled as a collection of simple harmonic oscillators. For the Markovian dynamics, MIN and the concurrence decrease monotonically with the scaled time and the decoherence time of the former is longer than that of the latter. While for the non-Markovian dynamics, MIN can revive for finite time periods after its disappearance immediately. With a comparison, the concurrence can revive for finite time periods after its complete disappearance which lasts for some time. The MIN takes a zero value for some discrete time points while the concurrence takes a zero value for finite time periods. In this sense, we can say that the MIN is more robust than the concurrence to decoherence. Finally, the non-Markovianity measure has been examined and we find that the strong non-Markovianity of the dynamical process corresponds to a large amplitude of the revival of MIN and the concurrence.

DOI: 10.1142/s021797921650260x

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