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arXiv · 1210.8311

Geometric Measure of Pairwise Quantum Discord for Superpositions of Multipartite Generalized Coherent States

M. Daoud·R. Ahl Laamara
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Abstract

We give the explicit expressions of the pairwise quantum correlations present in superpositions of multipartite coherent states. A special attention is devoted to the evaluation of the geometric quantum discord. The dynamics of quantum correlations under a dephasing channel is analyzed. A comparison of geometric measure of quantum discord with that of concurrence shows that quantum discord in multipartite coherent states is more resilient to dissipative environments than is quantum entanglement. To illustrate our results, we consider some special superpositions of Weyl-Heisenberg, SU(2) and SU(1,1) coherent states which interpolate between Werner and Greenberger-Horne-Zeilinger states.

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M. Daoud, R. Ahl Laamara. 2012-10-31. Geometric Measure of Pairwise Quantum Discord for Superpositions of Multipartite Generalized Coherent States. https://doi.org/10.1016/j.physleta.2012.06.005

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