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arXiv · 1901.04264

Practical issues of twin-field quantum key distribution

Feng-Yu Lu·Zhen-Qiang Yin·Rong-Wang·Guan-Jie Fan-Yuan·Shuang Wang·De-Yong He·Wei Chen·1Wei Huang·Bing-Jie Xu·Guang-Can Guo·Zheng-Fu Han
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Abstract

Twin-Field Quantum Key Distribution(TF-QKD) protocol and its variants, such as Phase-Matching QKD(PM-QKD), sending or not QKD(SNS-QKD) and No Phase Post-Selection TF-QKD(NPP-TFQKD), are very promising for long-distance applications. However, there are still some gaps between theory and practice in these protocols. Concretely, a finite-key size analysis is still missing, and the intensity fluctuations are not taken into account. To address the finite-key size effect, we first give the key rate of NPP-TFQKD against collective attack in finite-key size region and then prove it can be against coherent attack. To deal with the intensity fluctuations, we present an analytical formula of 4-intensity decoy state NPP-TFQKD and a practical intensity fluctuation model. Finally, through detailed simulations, we show NPP-TFQKD can still keep its superiority of high key rate and long achievable distance.

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Feng-Yu Lu, Zhen-Qiang Yin, Rong-Wang, Guan-Jie Fan-Yuan, Shuang Wang, De-Yong He, Wei Chen, 1Wei Huang, Bing-Jie Xu, Guang-Can Guo, Zheng-Fu Han. 2019-01-14. Practical issues of twin-field quantum key distribution. https://arxiv.org/abs/1901.04264

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