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arXiv · 1303.4830

Bell violation versus geometric measure of quantum discord and their dynamical behavior

Y. Yao·H. W. Li·M. Li·Z. Q. Yin·W. Chen·Z. F. Han
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Abstract

Motivated by recent numerous works on the interplay among various measures of quantum correlations, we aim to investigate the relationship between the violation of Clauser-Horne-Shimony-Holt (CHSH) Bell inequality and geometric measure of quantum discord for two-qubit systems. Exact lower and upper bounds of Bell violation versus geometric discord are obtained for a specific and significant class of states, Bell diagonal states, and the respective states which suffice those bounds are also characterized. The dynamical behavior of these two quantifiers is carefully analyzed in the presence of decoherence, including Markovian, non-Markovian, and non-back-action quantum environments. The results suggest that Bell violation is closely related to geometric discord, like its relationship with other entanglement monotones.

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Y. Yao, H. W. Li, M. Li, Z. Q. Yin, W. Chen, Z. F. Han. 2013-03-20. Bell violation versus geometric measure of quantum discord and their dynamical behavior. https://doi.org/10.1140/epjd%2Fe2012-30259-1

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