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arXiv · 1512.01772

Hilbert-Schmidt measure of pairwise quantum discord for three-qubit $X$ states

M. Daoud·R. Ahl Laamara·S. Seddik
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Abstract

The Hilbert-Schmidt distance between a mixed three-qubit state and its closest state is used to quantify the amount of pairwise quantum correlations in a tripartite system. Analytical expressions of geometric quantum discord are derived. A particular attention is devoted to two special classes of three-qubit $X$ states. They include three-qubit states of ${\rm W}$, ${\rm GHZ}$ and Bell type. We also discuss the monogamy property of geometric quantum discord in some mixed three-qubit systems.

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M. Daoud, R. Ahl Laamara, S. Seddik. 2015-12-06. Hilbert-Schmidt measure of pairwise quantum discord for three-qubit $X$ states. https://doi.org/10.1016/s0034-4877(15)30030-6

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