Free-running single-photon detection system for high-speed quenching and recovery

Abstract

The invention discloses a free-running single-photon detection system for high-speed quenching and recovery, which is characterized in that it includes: a SPAD and its peripheral circuit module 1, a discrimination and shaping module 2, a delay and amplification module 3, and an active quenching and Recovery module 4; wherein: SPAD and its peripheral circuit module 1 extract the avalanche signal and input it to the screening and shaping module 2, and the screening and shaping module 2 obtains the counting signal after screening and shaping; the counting signal is input to the delay and amplification module 3, and then It is divided into two paths, one path is passed through the operational amplifier to obtain the active quenching signal, and the other path is delayed to set the dead time and shaped to obtain the active recovery signal; the active quenching signal and the active recovery signal are respectively input to the active quenching and recovery module 4. The level signal output by the active quenching and recovery module 4 is connected to the anode of the SPAD to realize high-speed quenching and recovery of the SPAD. The system can simultaneously improve the detection efficiency and count rate of the single photon detector.

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...

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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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