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

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 نشر من قبل Alejo Salles
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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