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arXiv · 2007.12768

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
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Abstract

We build and test a single-photon detector based on a Si avalanche photodiode Excelitas 30902SH thermoelectrically cooled to -100 deg. C. Our detector has dark count rate below 1 Hz, 500 um 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.

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Elena Anisimova, Dmitri Nikulov, Simeng Simone Hu, Mark Bourgon, Sebastian Philipp Neumann, Rupert Ursin, Thomas Jennewein, Vadim Makarov. 2020-07-24. A low-noise single-photon detector for long-distance free-space quantum communication. https://doi.org/10.1140/epjqt/s40507-021-00111-0

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