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arXiv · 0706.4399

A criterion for entanglement in two two-level systems

E. Ferraro·A. Napoli·A. Messina
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Abstract

We prove a necessary and sufficient condition for the occurrence of entanglement in two two-level systems, simple enough to be of experimental interest. Our results are illustrated in the context of a spin star system analyzing the exact entanglement evolution of the central couple of spins.

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E. Ferraro, A. Napoli, A. Messina. 2007-06-29. A criterion for entanglement in two two-level systems. https://arxiv.org/abs/0706.4399

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