用于高速量子密码系统的1.25 GHz InGaAs/InP单光子探测器的研制

A 1.25 GHz InGaAs/InP Single-Photon Detector for High-Speed Quantum Cryptography

随着量子密码领域的快速发展,近红外单光子探测器的研究已经成为该领域的研究重点和技术制高点。报道了一种基于正弦门控与滤波技术的InGaAs/InP雪崩光电二极管(APD)高速单光子探测器,门控频率达到1.25GHz。在探测效率为10.3%时,暗计数概率为1.3×10-6/gate,后脉冲概率为5.6×10-5/ns。这种高速单光子探测器将大幅度提升量子密码系统的两个关键指标——密钥率和传输距离,为下一代高速量子密码系统的实用化应用奠定了基础。

With the rapid development of quantum cryptography, infrared single-photon detection becomes the key technology in this research field. A high-speed InGaAs/InP avalanche photodiode （APD） is presented based on single- photon detector with a 1.25 GHz gating frequency, using the technique of sine wave gating and filtering. When the detection efficiency is 10. 3%, dark count probability per gate is 1. 3 × 10-6 and the afterpulse probability per nanosecond is 5.6 × 10-5. This kind of detector can significantly enhance the performance of quantum cryptosystem in terms of secret key rate and transmission distance, which paves the way towards the practical applications of the next generation quantum cryptography.