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Quantum nonlocality obtained from local states by entanglement purification

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 نشر من قبل Philip Walther
 تاريخ النشر 2005
  مجال البحث فيزياء
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We have applied an entanglement purification protocol to produce a single entangled pair of photons capable of violating a CHSH Bell inequality from two pairs that individually could not. The initial poorly-entangled photons were created by a controllable decoherence that introduced complex errors. All of the states were reconstructed using quantum state tomography which allowed for a quantitative description of the improvement of the state after purification.



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