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arXiv · 1710.06354

Noise reduction in photon counting by exploiting spatial correlations

Jan Perina Jr·Vaclav Michalek·Ondrej Haderka
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Abstract

Joint photocount distributions of a weak twin beam acquired by an iCCD camera are analyzed with respect to the beam spatial correlations. A method for extracting these correlations from the experimental joint photocount distributions is suggested using a suitable statistical model that quantifies the contribution of spatial correlations to the joint photocount distributions. In detail, the profile of twin-beam intensity spatial cross-correlation function is revealed from the curve that gives the genuine mean photon-pair number (both photons from a pair are detected) as a function of the extent of the detection area. Also, the principle of reducing the noise in photon-number-resolving detection by using spatial correlations is experimentally demonstrated.

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Jan Perina Jr, Vaclav Michalek, Ondrej Haderka. 2017-10-17. Noise reduction in photon counting by exploiting spatial correlations. https://arxiv.org/abs/1710.06354

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