Quantum key distribution system against the probabilistic faint after-gate attack

• 来源期刊: 理论物理通讯（英文版）
• 年，卷（期）: 2020,（11）
• 所属期刊栏目: QUANTUM PHYSICS AND QUANTUM INFORMATION
• 页码范围: 43-47
• 页数: 5页
• 语种: 英文

摘要

In practical quantum key distribution (QKD) systems,a single photon-detector (SPD) is one of the most vulnerable components.Faint after-gate attack is a universal attack against the detector.However,the original faint after-gate attack can be discovered by monitoring the photocurrent.This paper presents a probabilistic generalization of the attack,which we refer to as probabilistic faint after-gate attack,by introducing probability control modules.Previous countermeasures for photocurrent monitoring may fail in detecting the eavesdropper under some specific probabilities.To mitigate this threat,we provide a method to determine the detectable boundary in the limitation of precision of photocurrent monitoring,and investigate the security of QKD systems under such boundaries using the weak randomness model.