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A necessary and sufficient criterion for multipartite separable states

Shengjun Wu·Xuemei Chen·Yongde Zhang
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Abstract

We present a necessary and sufficient condition for the separability of multipartite quantum states, this criterion also tells us how to write a multipartite separable state as a convex sum of separable pure states. To work out this criterion, we need to solve a set of equations, actually it is easy to solve these quations analytically if the density matrix of the given quantum state has few nonzero eigenvalues.

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Shengjun Wu, Xuemei Chen, Yongde Zhang. 2000-09-08. A necessary and sufficient criterion for multipartite separable states. https://doi.org/10.1016/s0375-9601(00)00595-8

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