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arXiv · 2505.05998

Genuine Multipartite Entanglement Measure Based on $\alpha$-concurrence

Ke-Ke Wang·Zhi-Wei Wei·Shao-Ming Fei
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Abstract

Quantifying genuine entanglement is a crucial task in quantum information theory. Based on the geometric mean of bipartite $\alpha$-concurrences among all bipartitions, we present a class of well-defined genuine multipartite entanglement (GME) measures G$\alpha$C with one parameter $\alpha$ for arbitrary multipartite states. We show that the G$\alpha$C is of continuity for any multipartite pure states. By utilizing the related symmetry, analytical results of G$\alpha$C are derived for any $n$-qubit GHZ states and W states, which show that the GHZ states are more genuinely entangled than the W states. With explicit examples, we demonstrate that the G$\alpha$C can distinguish different GME states that other GME measures fail to. These results justify the potential applications of G$\alpha$C in characterizing genuine multipartite entanglements.

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Ke-Ke Wang, Zhi-Wei Wei, Shao-Ming Fei. 2025-05-09. Genuine Multipartite Entanglement Measure Based on $\alpha$-concurrence. https://arxiv.org/abs/2505.05998

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