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arXiv · 2211.03266

A $(k+1)$-partite entanglement measure of $N$-partite quantum states

Yan Hong·Xianfei Qi·Ting Gao·Fengli Yan
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Abstract

The concept of \textquotedblleft the permutationally invariant part of a density matrx\textquotedblright constitutes an important tool for entanglement characterization of multiqubit systems. In this paper, we first present $(k+1)$-partite entanglement measure of $N$-partite quantum system, which possesses desirable properties of an entanglement measure. Moreover, we give strong bounds on this measure by considering the permutationally invariant part of a multipartite state. We give two definitions of efficient measurable degree of $(k+1)$-partite entanglement. Finally, several concrete examples are given to illustrate the effectiveness of our results.

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Yan Hong, Xianfei Qi, Ting Gao, Fengli Yan. 2022-11-07. A $(k+1)$-partite entanglement measure of $N$-partite quantum states. https://doi.org/10.1140/epjp%2Fs13360-023-04700-z

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