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Intercomparison of a Correlated-Photon-Based Method to Measure Detector Quantum Efficiency



Alan L. Migdall, Stefania Castelletto, Ivo P. Degiovanni, M L. Rastello


We report on the absolute calibration of photodetector quantum efficiency using correlated photon sources, performed independently at two laboratories, the National Institute of Standards and Technology (NIST) and the Istituto Elettrotecnico Nazionale (IEN).The correlated photons were generated via somewhat similar parametric downconversion setups in both laboratories. The quantum efficiency of a single photon counting avalanche photodiode module was measured in both the NIST and IEN setups. The aim was to use an interlaboratory comparison to demonstrate the inherent absoluteness of the photon correlation technique by showing its independence of the particular experimental setup used for downconversion generation.The ultimate goal of these investigations is the development of a robust measurement protocol that allows the uncertainties of individual measurements to be determined experimentally and verified operationally.
Applied Optics
No. 15


calibration, correlated photons, intercomparison, metrology, parametric downconversion, photon counting, primary standard, quantum efficiency, two-photons


Migdall, A. , Castelletto, S. , Degiovanni, I. and Rastello, M. (2002), Intercomparison of a Correlated-Photon-Based Method to Measure Detector Quantum Efficiency, Applied Optics, [online], (Accessed July 18, 2024)


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Created May 1, 2002, Updated February 17, 2017