Physical Review Applied

Afterpulse Analysis for Quantum Key Distribution

Guan‐Jie Fan‐Yuan, Chao Wang, Shuang Wang, Zhen−Qiang Yin, He Liu, Wei Chen, De‐Yong He, Zheng‐Fu Han, Guang‐Can Guo

Published Dec 13, 2018• 52 citations

Abstract

In optical quantum cryptography, the afterpulse effect is important for secure key generation in quantum key distribution (QKD), because it introduces additional error and leads to great deviation from the traditional analytical model, especially for high-speed systems. This study develops a different analytical model to make QKD systems more afterpulse-compatible, by exploiting the non-Markovian nature of the afterpulse. The optimized key rate obtained here is much higher, and thus the tolerance of the afterpulse effect can be significantly improved in practical QKD systems for secure communication.

DOI: 10.1103/physrevapplied.10.064032

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