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arXiv · 1601.02313

A note on one-way quantum deficit and quantum discord

Biao-Liang Ye·Shao-Ming Fei
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Abstract

One-way quantum deficit and quantum discord are two important measures of quantum correlations. We revisit the relationship between them in two-qubit systems. We investigate the conditions that both one-way quantum deficit and quantum discord have the same optimal measurement ensembles, and demonstrate that one-way quantum deficit can be derived from the quantum discord for a class of X states. Moreover, we give an explicit relation between one-way quantum deficit and entanglement of formation. We show that under phase damping channel both one-way quantum deficit and quantum discord evolve exactly in the same way for four parameters X states. Some examples are presented in details.

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Biao-Liang Ye, Shao-Ming Fei. 2016-01-11. A note on one-way quantum deficit and quantum discord. https://arxiv.org/abs/1601.02313

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