Low-noise photon counting above 100 × 106 counts per second with a high-efficiency reach-through single-photon avalanche diode system

Abstract

We demonstrate a method that allows a high-efficiency single-photon-avalanche diode (SPAD) with a thick absorption region (>10\u2009μm) to count single photons at rates significantly higher than previously demonstrated. We apply large (>30\u2009V) AC bias gates to the SPAD at 1\u2009GHz and detect minute avalanches with a discrimination threshold of 5(1) mV by means of radio frequency interferometry. We measure a reduction by a factor of\u2009≈500 in the average charge per avalanche when compared to operation in its traditional active-quenching module and a relative increase in >19% in detection efficiency at 850\u2009nm. The reduction in charge strongly suppresses self-heating effects in the diode that can degrade performance at high avalanche rates. We show that the single-photon detection system maintains high efficiency at count rates exceeding 108 s−1.