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arXiv · 2205.06394

Tightening monogamy and polygamy relations of unified entanglement in multipartite systems

Mei-Ming Zhang·Naihuan Jing·Hui Zhao
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Abstract

We study the monogamy and polygamy inequalities of unified entanglement in multipartite quantum systems. We first derive the monogamy inequality of unified-$(q, s)$ entanglement for multi-qubit states under arbitrary bipartition, and then obtain the monogamy inequalities of the $\alpha$th ($0\leq\alpha\leq\frac{r}{2}, r\geq\sqrt{2}$) power of entanglement of formation for tripartite states and their generalizations in multi-qubit quantum states. We also generalize the polygamy inequalities of unified-$(q, s)$ entanglement for multi-qubit states under arbitrary bipartition. Moreover, we investigate polygamy inequalities of the $\beta$th ($\beta\geq \max\{1, s\}, 0\leq s\leq s_0, 0\leq s_0\leq\sqrt{2}$) power of the entanglement of formation for $2\otimes2\otimes2$ and $n$-qubit quantum systems. Finally, using detailed examples, we show that the results are tighter than previous studies.

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Mei-Ming Zhang, Naihuan Jing, Hui Zhao. 2022-05-12. Tightening monogamy and polygamy relations of unified entanglement in multipartite systems. https://doi.org/10.1007/s11128-022-03479-9

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