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An extremely low-noise heralded single-photon source: a breakthrough for quantum technologies

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 نشر من قبل Paolo Traina
 تاريخ النشر 2013
  مجال البحث فيزياء
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Low noise single-photon sources are a critical element for quantum technologies. We present a heralded single-photon source with an extremely low level of residual background photons, by implementing low-jitter detectors and electronics and a fast custom-made pulse generator controlling an optical shutter (a LiNbO3 waveguide optical switch) on the output of the source. This source has a second-order autocorrelation g^{(2)}(0)=0.005(7), and an Output Noise Factor (defined as the ratio of the number of noise photons to total photons at the source output channel) of 0.25(1)%. These are the best performance characteristics reported to date.



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