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arXiv · 1210.8309

Quantum discord of Bell cat-states under amplitude damping

M. Daoud·R. Ahl Laamara
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Abstract

The evolution of pairwise quantum correlations of Bell cat-states under amplitude damping is examined using the concept of quantum discord which goes beyond entanglement. A closed expression of the quantum discord is explicitly derived. We used of the Koashi-Winter relation. A relation which facilitates the optimization process of the conditional entropy. We also discuss the temporal evolution of bipartite quantum correlations under a dephasing channel and compare the behaviors of quantum discord and entanglement whose properties are characterized through the concurrence.

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M. Daoud, R. Ahl Laamara. 2012-10-31. Quantum discord of Bell cat-states under amplitude damping. https://doi.org/10.1088/1751-8113%2F45%2F32%2F325302

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