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arXiv · 1106.4850

Quantum nonlocality does not imply entanglement distillability

Tamas Vertesi·Nicolas Brunner
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Abstract

Entanglement and nonlocality are both fundamental aspects of quantum theory, and play a prominent role in quantum information science. The exact relation between entanglement and nonlocality is however still poorly understood. Here we make progress in this direction by showing that, contrary to what previous work suggested, quantum nonlocality does not imply entanglement distillability. Specifically, we present analytically a 3-qubit entangled state that is separable along any bipartition. This implies that no bipartite entanglement can be distilled from this state, which is thus fully bound entangled. Then we show that this state nevertheless violates a Bell inequality. Our result also disproves the multipartite version of a longstanding conjecture made by Asher Peres.

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Tamas Vertesi, Nicolas Brunner. 2012-01-21. Quantum nonlocality does not imply entanglement distillability. https://doi.org/10.1103/physrevlett.108.030403

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