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Calibration of free-space and fiber-coupled single-photon detectors



Thomas Gerrits, Alan L. Migdall, Joshua C. Bienfang, John H. Lehman, Sae Woo Nam, Jolene D. Splett, Igor Vayshenker, Chih-Ming Wang


We measure the detection efficiency of single-photon detectors at wavelengths near 851 nm and 1533.6 nm. We investigate the spatial uniformity of one free-space-coupled single-photon avalanche diode and present a comparison between fusion-spliced and connectorized fiber-coupled single-photon detectors. We find that our expanded relative uncertainty for a single measurement of the detection efficiency is as low as 0.70 % for fiber-coupled measurements at 1533.6 nm and as high as 1.78 % for our free-space characterization at 851.7 nm. The detection-efficiency determination includes corrections for afterpulsing, dark count, and count-rate effects of the single-photon detector with the detection efficiency interpolated to operation at a specified detected count rate.


single photon detector, single photon detector calibration, quantum si


Gerrits, T. , Migdall, A. , Bienfang, J. , Lehman, J. , Nam, S. , Splett, J. , Vayshenker, I. and Wang, C. (2019), Calibration of free-space and fiber-coupled single-photon detectors, Metrologia, [online], (Accessed June 16, 2024)


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Created December 19, 2019, Updated September 30, 2020