We experimentally investigate a method of directly characterizing the photon number distribution of nonclassical light beams that is tolerant to losses and makes use only of standard binary detectors. This is achieved in a single measurement by calibrating the detector using some small amount of prior information about the source. We demonstrate the technique on a freely propagating heralded two-photon number state created by conditional detection of a two-mode squeezed state generated by a parametric downconverter.
@article{arxiv.quant-ph/0606170,
title = {Direct, Loss-Tolerant Characterization of Nonclassical Photon Statistics},
author = {Daryl Achilles and Christine Silberhorn and Ian A. Walmsley},
journal= {arXiv preprint arXiv:quant-ph/0606170},
year = {2007}
}