Abstract:
An NIR band single-photon detector(SPD), based on GPQC with balanced APD-PIN junction capacitance and InGaAs/InP avalanche photodiode, was designed which was able to work in wide gating frequency range. The SPD was driven by a pulsed gate signal of any frequency below 200 MHz, which had amplitude of 10 Vpp and pulse duration of approximately 1 ns. A novel GPQC was devised based on high-frequency PIN diode that had similar capacitive characteristics compared with APDs, such that the low-frequency portion of capacitive response of the APD was suppressed. Subsequently, a group of 9th ordered Bessel LC low-pass filters(LPF) were used to suppress the residual high-frequency portion. At the temperature of -52 ℃ and gating frequency ranged from 0.1-200 MHz, the dark count probability and afterpulse probability at detection efficiency of 10% were below 610-6/gate, 1.9%, respectively, and the highest detection efficiency reached 26.4%.