Dependence of InGaAs/InP avalanche photodiode based single photon detector’s noise characteristics on the photodiode’s active area

Nowadays the best single photon detectors from a practical view are those based on InGaAs/InP avalanche photodiodes, operating at a wavelength of 1.55 μm. In this work the characteristics of such a detector of our development are studied, while operating in Geiger mode with a synchronization frequency of 312.5 MHz. The dependence of quantum efficiency and noise levels on the active area are studied.