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arXiv · 0812.2445

Characterizing heralded single-photon sources with imperfect measurement devices

M. Razavi·I. Söllner·E. Bocquillon·C. Couteau·R. Laflamme·G. Weihs
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Abstract

Any characterization of a single-photon source is not complete without specifying its second-order degree of coherence, i.e., its $g^{(2)}$ function. An accurate measurement of such coherence functions commonly requires high-precision single-photon detectors, in whose absence, only time-averaged measurements are possible. It is not clear, however, how the resulting time-averaged quantities can be used to properly characterize the source. In this paper, we investigate this issue for a heralded source of single photons that relies on continuous-wave parametric down-conversion. By accounting for major shortcomings of the source and the detectors--i.e., the multiple-photon emissions of the source, the time resolution of photodetectors, and our chosen width of coincidence window--our theory enables us to infer the true source properties from imperfect measurements. Our theoretical results are corroborated by an experimental demonstration using a PPKTP crystal pumped by a blue laser, that results in a single-photon generation rate about 1.2 millions per second per milliwatt of pump power. This work takes an important step toward the standardization of such heralded single-photon sources.

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M. Razavi, I. Söllner, E. Bocquillon, C. Couteau, R. Laflamme, G. Weihs. 2009-09-12. Characterizing heralded single-photon sources with imperfect measurement devices. https://doi.org/10.1088/0953-4075%2F42%2F11%2F114013

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