Gigahertz sine-wave gate-control low-pass filtering ultrared single-photon detector

Abstract

The invention relates to the fields of quantum secret communication, weak ultrared detection, and the like, and provides a ultrared single-photon detector. The ultrared single-photon detector comprises a sine-wave gate-control power source, an In-Ga-As-In-P avalanche photodiode circuit, a DC voltage baising circuit, a semiconductor temperature-control circuit, a low-pass filter, a high-speed wideband amplifier, a ultra-high-speed comparator and a counter, wherein sine waves which have the frequency of gigahertz (GHz) and are output by the sine-wave gate-control power source are used as gate control signals of the In-Ga-As-In-P avalanche photodiode circuit, and spike noise caused by junction capacitance differential effect for the low pass filter is used for filtering in a low-pass mode. The gigahertz sine-wave gate-control low-pass filtering ultrared single-photon detector solves the problem of spike noise interference in the prior art, increases the detection sensitivity of avalanchesignals and is used for detecting GHz high-speed ultrared photon.

Description

technical field [0001] The invention relates to the fields of quantum secret communication and weak infrared light detection, and is an infrared single-photon detector. Background technique [0002] A single photon detector is an optoelectronic device specially used for single photon detection, and an infrared single photon detector working at a communication wavelength (1310-1550nm) is a key device in quantum secure communication. Infrared single-photon detectors are also used in quantum computing, optical ranging, fiber optic sensing, extremely weak light detection and interference, and other fields. [0003] At present, there are mainly the following methods for infrared single-photon detection: infrared single-photon detection using avalanche photodiodes (APDs) and superconducting single-photon detection methods. In superconducting single photon detection, the working temperature of the photosensitive element is extremely low, about 4K, which requires huge and expensive...

AI Technical Summary

Problems solved by technology

For high-speed infrared single-photon detectors, the above method cannot be used. In order to overcome the post-pulse effect under high-speed detection conditions, the photocurrent generated by single photons inside the APD must be further reduced, which will cause the avalanche photoelectric signal to be very weak, so It is necessary to further increase the amplification gain of the avalanche photoelectric signal and improve the sensitivity of the detector, so that the avalanche photoelectric signal can be effectively detected

Due to the junction capacitance effect of the APD, the gating signal will generate spike noise after passing through the APD. If the amplification gain of the avalanche signal is too high, the avalanche signal and the noise signal will be amplified at the same time, which will seriously interfere with the detection of the photoelectric avalanche signal. The signal is generally more than 2 orders of magnitude larger than the avalanche signal

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