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arXiv · 1805.09952

Practical gigahertz quantum key distribution robust against channel disturbance

Shuang Wang·Wei Chen·Zhen-Qiang Yin·De-Yong He·Cong Hui·Peng-Lei Hao·Guan-Jie Fan-Yuan·Chao Wang·Li-Jun Zhang·Jie Kuang·Shu-Feng Liu·Zheng Zhou·Yong-Gang Wang·Guang-Can Guo·Zheng-Fu Han
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Abstract

Quantum key distribution (QKD) provides an attractive solution for secure communication. However, channel disturbance severely limits its application when a QKD system is transfered from the laboratory to the field. Here, a high-speed Faraday-Sagnac-Michelson QKD system is proposed that can automatically compensate for the channel polarization disturbance, which largely avoids the intermittency limitations of environment mutation. Over a 50-km fiber channel with 30-Hz polarization scrambling, the practicality of this phase-coding QKD system was characterized with an interference fringe visibility of 99:35% over 24 hours, and a stable secure key rate of 306k bits/s over 7 days without active polarization alignment.

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Shuang Wang, Wei Chen, Zhen-Qiang Yin, De-Yong He, Cong Hui, Peng-Lei Hao, Guan-Jie Fan-Yuan, Chao Wang, Li-Jun Zhang, Jie Kuang, Shu-Feng Liu, Zheng Zhou, Yong-Gang Wang, Guang-Can Guo, Zheng-Fu Han. 2018-05-25. Practical gigahertz quantum key distribution robust against channel disturbance. https://doi.org/10.1364/ol.43.002030

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