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arXiv · 1904.07899

Activation of nonlocality in bound entanglement

Lucas Tendick·Hermann Kampermann·Dagmar Bruß
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Abstract

We discuss the relation between entanglement and nonlocality in the hidden nonlocality scenario. Hidden nonlocality signifies nonlocality that can be activated by applying local filters to a particular state that admits a local hidden-variable model in the Bell scenario. We present a fully-biseparable three-qubit bound entangled state with a local model for the most general (non-sequential) measurements. This proves for the first time that bound entangled states can admit a local model for general measurements. We furthermore show that the local model breaks down when suitable local filters are applied. Our results demonstrate the first example of activation of nonlocality in bound entanglement. Hence, we show that genuine hidden nonlocality does not imply entanglement distillability.

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Lucas Tendick, Hermann Kampermann, Dagmar Bruß. 2019-04-16. Activation of nonlocality in bound entanglement. https://doi.org/10.1103/physrevlett.124.050401

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