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arXiv · 0909.1634

Local correlations of mixed two-qubit states

Fu-Lin Zhang·Jing-Ling Chen·Chang-Liang Ren·Ming-Jun Shi
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Abstract

The quantum probability distribution arising from single-copy von Neumann measurements on an arbitrary two-qubit state is decomposed into the local and nonlocal parts, in the approach of Elitzur, Popescu and Rohrlich [A. Elitzur, S. Popescu, and D. Rohrlich, Phys. Lett. A 162, 25 (1992)]. A lower bound of the local weight is proved being connected with the concurrence of the state $p_L^{\max}= 1-\mathcal{C}(\rho)$. The local probability distributions for two families of mixed states are constructed independently, which accord with the lower bound.

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Fu-Lin Zhang, Jing-Ling Chen, Chang-Liang Ren, Ming-Jun Shi. 2009-09-09. Local correlations of mixed two-qubit states. https://doi.org/10.1016/j.physleta.2010.04.004

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