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Optimal spin squeezing inequalities detect bound entanglement in spin models

Geza Toth·Christian Knapp·Otfried Gühne·Hans J. Briegel
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Abstract

We determine the complete set of generalized spin squeezing inequalities. These are entanglement criteria that can be used for the experimental detection of entanglement in a system of spin-1/2 particles in which the spins cannot be individually addressed. They can also be used to show the presence of bound entanglement in the thermal states of several spin models.

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Geza Toth, Christian Knapp, Otfried Gühne, Hans J. Briegel. 2008-01-18. Optimal spin squeezing inequalities detect bound entanglement in spin models. https://doi.org/10.1103/physrevlett.99.250405

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