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Non-local geometric phase in two-photon interferometry

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 نشر من قبل Anders Kastberg
 تاريخ النشر 2011
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Anthony Martin




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We report the experimental observation of the nonlocal geometric phase in Hanbury Brown-Twiss polarized intensity interferometry. The experiment involves two independent, polar- ized, incoherent sources, illuminating two polarized detectors. Varying the relative polarization angle between the detectors introduces a geometric phase equal to half the solid angle on the Poincare sphere traced out by a pair of single photons. Local measurements at either detector do not reveal the effect of the geometric phase, which appears only in the coincidence counts between the two detectors, showing a genuinely nonlocal effect. We show experimentally that coincidence rates of photon arrival times at separated detectors can be controlled by the two photon geometric phase. This effect can be used for manipulating and controlling photonic entanglement.



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