Ultraviolet Single Photon Detection With Geiger-Mode 4H-SiC Avalanche Photodiodes

We report 4H-SiC avalanche photodiodes operated in Geiger mode for single photon detection at 265 nm. At room temperature, the single photon detection efficiency is 14% with a dark count probability of 1.7 x 10-4. Since the external quantum efficiency is 21% at 265 nm, it follows that 65% of the absorbed photons are counted as avalanche events. The jitter of the photodiodes is also characterized.