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arXiv · 2602.04760

Quantifying the Operational Cost of Multipartite Entanglement

Francois Payn·Michele Minervini·Davide Girolami
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Abstract

Multipartite entanglement determines the strength and range of interactions in many-body quantum systems. Yet, it is hard to evaluate it, due to the complex structures of quantum states. Here, we introduce a generic method to quantify the k <= N-partite entanglement of an N-particle system, by maximizing an arbitrary bipartite entanglement measure within subsystems of size up to k. The resulting classification of multipartite states captures their experimental cost: creating a k-partite entangled state requires at least k-1 two-particle entangling gates. Further, we analytically calculate the newly defined k-partite entanglement of formation, which generalizes an important bipartite entanglement measure, in several classes of states, including the W states of any dimension.

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Francois Payn, Michele Minervini, Davide Girolami. 2026-02-04. Quantifying the Operational Cost of Multipartite Entanglement. https://arxiv.org/abs/2602.04760

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