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Multipartite quantum correlation and entanglement in four-qubit pure states

Yan-Kui Bai·Dong Yang·Z. D. Wang
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Abstract

Based on the quantitative complementarity relations, we analyze thoroughly the properties of multipartite quantum correlations and entanglement in four-qubit pure states. We find that, unlike the three-qubit case, the single residual correlation, the genuine three- and four-qubit correlations are not suited to quantify entanglement. More interestingly, from our qualitative and numerical analysis, it is conjectured that the sum of all the residual correlations may constitute a good measure for the total multipartite entanglement in the system.

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Yan-Kui Bai, Dong Yang, Z. D. Wang. 2007-09-01. Multipartite quantum correlation and entanglement in four-qubit pure states. https://doi.org/10.1103/physreva.76.022336

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