A low-noise single-photon detector for long-distance free-space quantum communication
Elena Anisimova, Dmitri Nikulov, Simeng Simone Hu, Mark Bourgon, Sebastian Philipp Neumann, Rupert Ursin, Thomas Jennewein, Vadim Makarov · EPJ Quantum Technology · 2021
Abstract We build and test a single-photon detector based on a Si avalanche photodiode Excelitas 30902SH thermoelectrically cooled to −100∘C. Our detector has dark count rate below 1 Hz, $500\ \mu\mathrm{m}$ 500 μ m diameter photosensitive area, photon detection efficiency around 50%, afterpulsing less than 0.35%, and timing jitter under 1 ns. These characteristics make it suitable for long-distance free-space quantum communication links, which we briefly discuss. We also report an improved method that we call long-time afterpulsing analysis, used to determine and visualise long trap lifetimes at different temperatures.