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arXiv · 0707.2809

Multipartite positive-partial-transpose inequalities exponentially stronger than local reality inequalities

Koji Nagata
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Abstract

We show that positivity of {\it every} partial transpose of $N$-partite quantum states implies new inequalities on Bell correlations which are stronger than standard Bell inequalities by a factor of $2^{(N-1)/2}$. A violation of the inequality implies the system is in a bipartite distillable entangled state. It turns out that a family of $N$-qubit bound entangled states proposed by Dür {[Phys. Rev. Lett. {\bf 87}, 230402 (2001)]} violates the inequality for $N\geq 4$.

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Koji Nagata. 2007-07-18. Multipartite positive-partial-transpose inequalities exponentially stronger than local reality inequalities. https://doi.org/10.1103/physreva.76.024101

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