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arXiv · 1208.1554

Dynamics of quantum discord in asymmetric and local non-Markovian environments

Xiang Hao·Tao Pan·Jinqiao Sha
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Abstract

The non-Markovian decoherence of quantum and classical correlations is analytically obtained when two qubits are asymmetrically subjected to the bit flip channel and phase flip channel. For one class of initial mixed states, quantum correlations quantified by quantum discord decay synchronously with classical correlations. The discovery that the decaying rates of quantum and classical correlations suddenly change at the characteristic time is physically interpreted by the distance from quantum state to the closest classical states. In a large time interval, quantum correlations are greater than classical correlations. The quantum and classical correlations can be preserved over a longer period of time via the kernel characterizing the environment memory effects.

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Xiang Hao, Tao Pan, Jinqiao Sha. 2012-08-08. Dynamics of quantum discord in asymmetric and local non-Markovian environments. https://arxiv.org/abs/1208.1554

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