Self-triggered method for characterization of single-photon detectors

Single-photon avalanche photodiodes (SPADs) are instruments capable of measuring light at the single-photon level. Some important features of these devices must be correctly characterized for reliable application. In this paper, I present a high-resolution self-triggered method for characterization of SPADs based on the analysis of the time intervals between consecutive detection events with the detector under continuous-wave illumination. The self-triggered method is employed for characterization of the detection dead time-a limiting feature for the maximum counting rate achievable under free-running or gated modes--and of the temporal gate width--an important parameter when the detector is operated under gated mode. The measurement results are presented and the method is experimentally validated.