Noise reduction in photon counting by exploiting spatial correlations

TL;DR

This paper presents a method to analyze and utilize spatial correlations in twin photon beams to reduce noise in photon counting, enhancing the accuracy of photon-number-resolving detection.

Contribution

It introduces a statistical model to extract spatial correlations from joint photocount distributions and demonstrates noise reduction using these correlations.

Findings

Spatial correlations can be quantified from photocount data.

The method reveals the intensity cross-correlation profile of twin beams.

Noise in photon counting can be reduced by exploiting spatial correlations.

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.