High-speed-quenching and high-speed-recovery free-operation single-photon detection system

Abstract

The invention discloses a high-speed-quenching and high-speed-recovery free-operation single-photon detection system. The system is characterized in that the system includes an SPAD (single-photon avalanche diode), a peripheral circuit module 1 thereof, an identification and shaping module 2, a time delay and amplification module 3 and an active quenching and recovery module 4; the SPAD and the peripheral circuit module 1 thereof extract avalanche signals and input the avalanche signals to the identification and shaping module 2; the identification and shaping module 2 identifies and shapes the avalanche signals so as to obtain counting signals; the counting signals are inputted to the time delay and amplification module 3 and then are divided into two paths, wherein one path passes through an operational amplifier, so that active quenching signals can be obtained, and the other path is subjected to dead time setting delay and shaping, so that active recovery signals are obtained; the active quenching signals and the active recovery signals are inputted to the active quenching and recovery module 4; and the electric level signals of the active quenching and recovery module 4 are connected into the anode of the SPAD, so that the high-speed quenching and high-speed recovery of the SPAD are realized. With the system adopted, the detection efficiency and counting rate of a single-photon detector can be improved.

Description

technical field [0001] The invention relates to the technical fields of single-photon detection and quantum communication, in particular to a free-running single-photon detection system with high-speed quenching and recovery. Background technique [0002] Semiconductor single-photon detectors are essential tools for ultra-weak light detection, and have a wide range of application requirements in many fields. The basic working principle of the semiconductor single photon detector is that the single photon avalanche photodiode (SPAD) works in the Geiger mode, that is, the reverse bias voltage of the SPAD exceeds its avalanche breakdown voltage. When the incident single photon is absorbed, a pair of carriers will be generated. Due to the impact ionization effect, the carriers form an avalanche effect and finally output a macroscopic current. After detecting the avalanche signal, the back-end quenching circuit will output a detection signal, and at the same time reset the circu...

AI Technical Summary

Problems solved by technology

[0003] Due to the limitation of detection technology, ordinary commercial single-photon detectors will reduce the overvoltage when SPAD is working and set a longer dead time in order to meet the balance requirements of dark count rate and post-pulse probability, resulting in the decrease of detection efficiency and count rate of the detector. The potential has not been fully realized, and it cannot meet some applications that require high detection efficiency and high count rate

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