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arXiv · 1312.4462

Inseparability criteria based on bipartitions of $N$-spin systems

Asoka Biswas
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Abstract

We present a new set of inseparabilty inequalities to detect entanglement in $N$-spin states. These are based on negative partial transposition and involve collective spin-spin correlations of any two partitions of the entire system. They also reveal the rich texture of partial separability for different partition and can discriminate between GHZ-type and W-type entanglement, as well. We introduce a new concept of relative entanglement of two different systems and two different partitions in a spin-ensemble. These criteria can be applicable to non-symmetric states and states with odd or even $N$.

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Asoka Biswas. 2013-12-16. Inseparability criteria based on bipartitions of $N$-spin systems. https://arxiv.org/abs/1312.4462

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