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Interpreting concurrence in terms of covariances in a generalized spin star system

F. Palumbo·A. Napoli·A. Messina
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Abstract

The quantum dynamics of M pairwise coupled spin 1/2 is analyzed and the time evolution of the entanglement get established within a prefixed couple of spins is studied. A conceptual and quantitative link between the concurrence function and measurable quantities is brought to light providing a physical interpretation for the concurrence itself as well as a way to measure it. A generalized spin star system is exactly investigated showing that the entanglement accompanying its rich dynamics is traceable back to the covariance of appropriate commuting observables of the two spins.

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F. Palumbo, A. Napoli, A. Messina. 2006-06-20. Interpreting concurrence in terms of covariances in a generalized spin star system. https://arxiv.org/abs/quant-ph/0606163

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