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arXiv · 2607.21367

A solution to 2-copy distillability of Werner states

Jinshi Fu·Li Gao·Sang-Jun Park
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Abstract

Entanglement distillation is a fundamental task in quantum information theory. In this work, we prove that Werner states in arbitrary dimension are 2-copy distillable if and only if they are 1-copy distillable. This answers the longstanding open question of the 2-copy distillability of Werner states. This is an important step on determining whether every non-positive partial transpose (NPT) state is distillable, which remains one of the central open problems in the field of entanglement distillation.

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Jinshi Fu, Li Gao, Sang-Jun Park. 2026-07-23. A solution to 2-copy distillability of Werner states. https://arxiv.org/abs/2607.21367

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