Fluctuation Analysis of Decoy State QKD with Finite Data-Set Size

Weilong Wang, Xiangdong Meng, Yangyang Fei +1 more

Xuan Wen, Qiong Li, Hongjuan Wang +2 more

Tang Shao-Jie, Rongzhen Jiao

Decoy state method quantum key distribution (QKD) is one of the promising practical solutions for BB84 QKD with coherent light pulses. The number of data-set size in practical QKD protocol is always finite, which will cause statistical fluctuations. In this paper, we apply absolutely statistical fluctuation to amend the yield and error rate of the quantum state. The relationship between exchanged number of quantum signals and key generation rate is analyzed in our simulation, which offers a useful reference for experiment.

Hong-Wei Li, Yibo Zhao, Zhen−Qiang Yin +4 more

Chun Hua Zhou, Yu Zhi Zhou, Yang-Bin Xu +5 more

The decoy state quantum key distribution (QKD) protocol is proven to be an effective strategy against the photon number splitting attack. It was shown that the 1-decoy state protocol, easier to implement in the practical QKD system, outperforms the 2-decoy state protocol for block sizes of up to 108 bits. How intensity fluctuations influence the performance of the 1-decoy state protocol with finite resources remains a pending issue. In this paper, we present a finite-key analysis of the 1-decoy state protocol with intensity fluctuations and obtain the secret key rate formula about intensity fluctuations. Our numerical simulation results show that the stronger the intensity fluctuations, the lower the secret key rate for a small data block size of a few bits. Our research can provide theoretical implications for the selection of data size in the QKD system with intensity fluctuations.

Konstantinos Gkouliaras, Vasileios Theos, Stylianos Chatzidakis