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arXiv · 1406.1964

Geometric global quantum discord of two-qubit X states

Wen-Chao Qiang·Hua-Ping Zhanga·Lei Zhang
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Abstract

Xu [Jianwei Xu, J. Phys. A: Math. Theor. 45 405304 (2012)] generalized geometric quantum discord [B.Dakic, V. Vedral, and C . Brukner, Phys. Rev. Lett. 105 190502 (2010)] to multipartite states and proposed the geometric global quantum discord. In this paper, we first derive the analytical formulas of the geometric global quantum discord and geometric quantum discord for two-qubit X states, respectively. Second, we give five concrete examples to demonstrate the use of our formulas. Finally, we prove that the geometric quantum discord is a tight lower bound of the geometric global quantum discord.

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Wen-Chao Qiang, Hua-Ping Zhanga, Lei Zhang. 2014-06-08. Geometric global quantum discord of two-qubit X states. https://doi.org/10.1007/s10773-015-2823-8

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