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Entanglement tensor for a general pure multipartite quantum state

Hoshang Heydari·Gunnar Björk
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Abstract

We propose an entanglement tensor to compute the entanglement of a general pure multipartite quantum state. We compare the ensuing tensor with the concurrence for bipartite state and apply the tensor measure to some interesting examples of entangled three-qubit and four-qubit states. It is shown that in defining the degree of entanglement of a multi-partite state, one needs to make assumptions about the willingness of the parties to cooperate. We also discuss the degree of entanglement of the multi-qubit $\ket{W_{M}}$-states.

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Hoshang Heydari, Gunnar Björk. 2004-10-15. Entanglement tensor for a general pure multipartite quantum state. https://arxiv.org/abs/quant-ph/0410124

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