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arXiv · 2608.29707

Tight Global Bound on Pairwise Entanglement of Formation in Three-Qubit Systems

Wei Song·Xiao-Lan Zong·Ming Yang
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Abstract

We derive a global bound on the sum of pairwise squared entanglement of formation in three-qubit systems. The bound is tight and can be saturated by states containing a maximally entangled bipartite pair with an uncorrelated third qubit. Moreover, using this relation, we can map the three bipartite entanglements to three coordinates, such that any three-qubit state corresponds to a point in three-dimensional space, thereby endowing this global inequality with a very natural geometric picture. Accordingly, the dynamical evolution can be interpreted as trajectories in this geometric space; we select representative initial states and investigate the dynamical behavior of the three pairwise entanglements under various Markovian noise models.

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Wei Song, Xiao-Lan Zong, Ming Yang. 2026-08-30. Tight Global Bound on Pairwise Entanglement of Formation in Three-Qubit Systems. https://arxiv.org/abs/2608.29707

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