Evaluation of quantum efficiency of InGaAs/InP single-photon detectors in quantum key distribution systems

In this paper an important parameter of single-photon detectors, such as quantum efficiency, is considered. Errors in determining this parameter lead to significant errors in the parameters of a quantum key distribution system, where such detectors find their application. Three models are proposed to estimate photon detection efficiency or quantum efficiency and their main advantages and disadvantages are considered. A special experimental setup has been developed to carry out validation of the presented models on experimental data. It was found that at low values of laser radiation power the dependent and empirical models give good results, and the independent model is not applicable.