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arXiv · 2307.02364

High-rate quantum key distribution exceeding 110 Mb/s

Wei Li·Likang Zhang·Hao Tan·Yichen Lu·Sheng-Kai Liao·Jia Huang·Hao Li·Zhen Wang·Hao-Kun Mao·Bingze Yan·Qiong Li·Yang Liu·Qiang Zhang·Cheng-Zhi Peng·Lixing You·Feihu Xu·Jian-Wei Pan
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Abstract

Quantum key distribution (QKD) can provide fundamentally proven security for secure communication. Toward application, the secret key rate (SKR) is a key figure of merit for any QKD system. So far, the SKR has been limited to about a few megabit-per-second. Here we report a QKD system that is able to generate key at a record high SKR of 115.8 Mb/s over 10-km standard fibre, and to distribute key over up to 328 km of ultra-low-loss fibre. This attributes to a multi-pixel superconducting nanowire single-photon detector with ultrahigh counting rate, an integrated transmitter that can stably encode polarization states with low error, a fast post-processing algorithm for generating key in real time and the high system clock-rate operation. The results demonstrate the feasibility of practical high-rate QKD with photonic techniques, thus opening its possibility for widespread applications.

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Wei Li, Likang Zhang, Hao Tan, Yichen Lu, Sheng-Kai Liao, Jia Huang, Hao Li, Zhen Wang, Hao-Kun Mao, Bingze Yan, Qiong Li, Yang Liu, Qiang Zhang, Cheng-Zhi Peng, Lixing You, Feihu Xu, Jian-Wei Pan. 2023-07-05. High-rate quantum key distribution exceeding 110 Mb/s. https://doi.org/10.1038/s41566-023-01166-4

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