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arXiv · 1204.5868

Global Quantum discord of multi-qubit states

Jianwei Xu
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Abstract

Global quantum discord (GQD), proposed by Rulli and Sarandy [Phys. Rev. A \textbf{84}, 042109 (2011)], is a generalization of quantum discord to multipartite states. In this paper, we provide an equivalent expression for GQD, and obtain the analytical expressions of GQD for two classes of multi-qubit states. The phenomena of sudden transition and freeze of GQD are also discussed.

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Jianwei Xu. 2012-04-26. Global Quantum discord of multi-qubit states. https://doi.org/10.1016/j.physleta.2012.11.054

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