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MiS Preprint
66/2020
Necessary conditions for classifying m-separability of multipartite entanglements
Wen Xu, Chuan-Jie Zhu, Zhu-Jun Zheng and Shao-Ming Fei
Abstract
We study the norms of the Bloch vectors for arbitrary $n$-partite quantum states. A tight upper bound of the norms is derived for $n$-partite systems with different individual dimensions. These upper bounds are used to deal with the separability problems. Necessary conditions are presented for $\mathbf m$-separable states in $n$-partite quantum systems. Based on the upper bounds, classification of multipartite entanglement is illustrated with detailed examples.