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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, Oliver T. Slattery, Jolene D. Splett, Igor Vayshenker, Chih-Ming Wang


We present our measurements of the detection efficiency of free-space and fiber-coupled single- photon detectors at wavelengths near 851 nm and 1533.6 nm. We investigate the spatial uniformity of one free-space-coupled silicon single-photon avalanche diode (SPAD) 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 0.7 % for fiber-coupled measurements at 1533.6 nm and as high as 1.8 % for our free-space characterization at 851.8 nm.
Conference Dates
September 14-17, 2020
Conference Location
virtual, MD
Conference Title
Quantum 2.0 Conference


single photon detectors, single photon detector calibration, single photon metrology


Gerrits, T. , Migdall, A. , Bienfang, J. , Lehman, J. , Nam, S. , Slattery, O. , Splett, J. , Vayshenker, I. and Wang, C. (2020), Calibration of free-space and fiber-coupled single-photon detectors, Quantum 2.0 Conference, virtual, MD, [online], (Accessed June 19, 2024)


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Created September 13, 2020, Updated September 30, 2020