Quantum Efficiency of a Single Photon Detector Experimental Estimation

The dependence of the quantum efficiency of the single photon detector as a function of the average number of photons in the laser pulse is investigated. A method of estimation of quantum efficiency of a single photon detector in the operating mode of a quantum key distribution system operating according to the BB84 protocol is proposed. On the basis of an academic installation of the key quantum distribution system EMQOS 1.0 of the company QRate the experimental researches are executed and dependences of quantum efficiency of the detector of single photons from an average number of photons falling on the detector at various lengths of pulse sequences are received. Practical recommendations are given for the use of the proposed technique to estimate the quantum efficiency of single photon detectors.