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arXiv · 1312.2636

Free-running InGaAs single photon detector with 1 dark count per second at 10% efficiency

Boris Korzh·Nino Walenta·Tommaso Lunghi·Nicolas Gisin·Hugo Zbinden
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Abstract

We present a free-running single photon detector for telecom wavelengths based on a negative feedback avalanche photodiode (NFAD). A dark count rate as low as 1 cps was obtained at a detection efficiency of 10%, with an afterpulse probability of 2.2% for 20 μs of deadtime. This was achieved by using an active hold-off circuit and cooling the NFAD with a free-piston stirling cooler down to temperatures of -110${^o}$C. We integrated two detectors into a practical, 625 MHz clocked quantum key distribution system. Stable, real-time key distribution in presence of 30 dB channel loss was possible, yielding a secret key rate of 350 bps.

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Boris Korzh, Nino Walenta, Tommaso Lunghi, Nicolas Gisin, Hugo Zbinden. 2014-12-03. Free-running InGaAs single photon detector with 1 dark count per second at 10% efficiency. https://doi.org/10.1063/1.4866582

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