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Enhanced signal-to-noise ratio in Hanbury Brown Twiss interferometry by parametric amplification

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 نشر من قبل Chenglong You
 تاريخ النشر 2017
  مجال البحث فيزياء
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The Hanbury Brown Twiss (HBT) interferometer was proposed to observe intensity correlations of starlight to measure a stars angular diameter. As the intensity of light that reaches the detector from a star is very weak, one cannot usually get a workable signal-to-noise ratio. We propose an improved HBT interferometric scheme introducing optical parametric amplifiers into the system, to amplify the correlation signal, which is used to calculate the angular diameter. With the use of optical parametric amplifiers, the signal-to-noise ratio can be increased up to 400 percent.

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