Today I released a new paper, Comparison of architectures for approximating number-resolving photo-detection using non-number-resolving detectors, with my collaborators James Webb, Elanor Huntington and Tim Ralph.
Photo-detection is an essential requirement in any optical quantum information processing application. Unfortunately, presently available photo-detectors are limited in that they cannot resolve photon number. That is, they can tell if photons were present, but not how many there were. To remedy this, several schemes have been proposed for implementing number resolving photo-detection using non-number resolving detectors. In this paper we analyze these schemes in detail and compare their performance in different conditions. This gives the experimentalist insight into how best to construct these schemes for use in the laboratory.