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arXiv · 0908.3679

Separability criteria and entanglement witnesses for symmetric quantum states

Geza Toth·Otfried Gühne
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Abstract

We study the separability of symmetric bipartite quantum states and show that a single correlation measurement is sufficient to detect the entanglement of any bipartite symmetric state with a non-positive partial transpose. We also discuss entanglement conditions and entanglement witnesses for states with a positive partial transpose.

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Geza Toth, Otfried Gühne. 2009-12-17. Separability criteria and entanglement witnesses for symmetric quantum states. https://doi.org/10.1007/s00340-009-3839-7

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