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Ultra-bright source of polarization-entangled photons

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 نشر من قبل Andrew G. White
 تاريخ النشر 1998
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Paul G. Kwiat




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Using the process of spontaneous parametric down conversion in a novel two-crystal geometry, one can generate a source of polarization-entangled photon pairs which is orders of magnitude brighter than previous sources. We have measured a high level of entanglement between photons emitted over a relatively large collection angle, and over a 10-nm bandwidth. As a demonstration of the source intensity, we obtained a 242-$sigma$ violation of Bells inequalities in less than three minutes.



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