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arXiv · 1412.0398

Pairwise quantum and classical correlations in multi-qubits states via linear relative entropy

M. Daoud·R. Ahl Laamara·H. El Hadfi
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Abstract

The pairwise correlations in a multi-qubit state are quantified through a linear variant of relative entropy. In particular, we derive the explicit expressions of total, quantum and classical bipartite correlations. Two different bi-partioning schemes are considered. We discuss the derivation of closest product, quantum-classical and quantum-classical product states. We also investigate the additivity relation between the various pairwise correlations existing in pure and mixed states. As illustration, some special cases are examined.

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M. Daoud, R. Ahl Laamara, H. El Hadfi. 2014-12-01. Pairwise quantum and classical correlations in multi-qubits states via linear relative entropy. https://doi.org/10.1142/s021974991450035x

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