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arXiv · 0804.4703

Quantum Non-locality and Partial Transposition for Continuous-Variable Systems

Alejo Salles·Daniel Cavalcanti·Antonio Acín
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Abstract

A continuous-variable Bell inequality, valid for an arbitrary number of observers measuring observables with an arbitrary number of outcomes, was recently introduced in [Cavalcanti \emph{et al.}, Phys. Rev. Lett. {\bf 99}, 210405 (2007)]. We prove that any $n$-mode quantum state violating this inequality with quadrature measurements necessarily has a negative partial transposition. Our results thus establish the first link between nonlocality and bound entanglement for continuous-variable systems.

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Alejo Salles, Daniel Cavalcanti, Antonio Acín. 2008-07-25. Quantum Non-locality and Partial Transposition for Continuous-Variable Systems. https://doi.org/10.1103/physrevlett.101.040404

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