Detection Efficiency Measurement of Single-Photon Detectors Based on Spontaneous Parametric Scattering Process Using the Heterodyning Method

The article presents the various problems in the metrological support for the components of quantum information systems and uses the Klyshko reference method given in the international ETSI standard, which works on the principle of spontaneous parametric scattering effect. It is found that the measurement time has increased by an order of magnitude at noise level with a high power density at low frequencies when compared to desired signal level for single-photon detectors. So, the heterodyning method is proposed to increase the efficiency of signal accumulation. The method consists in accumulating a signal at a higher frequency and introducing modulation into the standard Klyshko scheme. The method proposed is simulated numerically and the signal-to-noise ratio is increased by a factor of 14 compared to simple signal accumulation has been established experimentally.