Figure 3From: A low-noise single-photon detector for long-distance free-space quantum communicationCharacterization setup. For DCR and detection efficiency measurements the output of the SPD is connected to the counter. For afterpulsing analysis the SPD output is connected to a time stamp unit (time tagger; TT). For breakdown voltage and timing jitter measurements the SPD is connected to the oscilloscope. XY translation stage allows to scan photosensitive area of the SPDBack to article page