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arXiv · 0709.4642

Multipartite entanglement in four-qubit cluster-class states

Yan-Kui Bai·Z. D. Wang
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Abstract

Based on quantitative complementarity relations (QCRs), we analyze the multipartite correlations in four-qubit cluster-class states. It is proven analytically that the average multipartite correlation $E_{ms}$ is entanglement monotone. Moreover, it is also shown that the mixed three-tangle is a correlation measure compatible with the QCRs in this kind of quantum states. More arrestingly, with the aid of the QCRs, a set of hierarchy entanglement measures is obtained rigorously in the present system.

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Yan-Kui Bai, Z. D. Wang. 2008-03-08. Multipartite entanglement in four-qubit cluster-class states. https://doi.org/10.1103/physreva.77.032313

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