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arXiv · 2512.24094

5-GHz chip-based quantum key distribution with 1Mbps secure key rate over 150 km

Guo-Wei Zhang·Sheng-Teng Zheng·You Xiao·Fang-Xiang Wang·Wen-Jing Ding·Dianpeng Wang·Penglei Hao·Li Zhang·Jia-Lin Chen·Yu-Yang Ding·Shuang Wang·De-Yong He·Zhen-Qiang Yin·Zheng Zhou·Hao Li·Lixing You·Guang-Can Guo·Wei Chen·Zheng-Fu Han
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Abstract

Quantum key distribution (QKD) enables secure communication by harnessing the fundamental principles of quantum physics, which inherently guarantee information-theoretic security and intrinsic resistance to quantum computing attacks. However, the secure key rate of QKD typically decreases exponentially with increasing channel distance. In this work, by developing a novel polarization-state preparation method, an ultra-low time-jitter laser source and superconducting nanowire single-photon detectors, we demonstrate a 5-GHz integrated QKD system featuring ultra-low quantum bit error rates (QBERs). The system achieves secure key rates of 1.076 Mbps at 150 km and 105 kbps at 200 km over standard single-mode fiber channels, respectively. Our system substantially enhances the secure key rate, enabling high-resolution video calls with one-time-pad encryption over intercity backbone QKD links. This work represents a significant step forward in the development of high-performance practical QKD systems.

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Guo-Wei Zhang, Sheng-Teng Zheng, You Xiao, Fang-Xiang Wang, Wen-Jing Ding, Dianpeng Wang, Penglei Hao, Li Zhang, Jia-Lin Chen, Yu-Yang Ding, Shuang Wang, De-Yong He, Zhen-Qiang Yin, Zheng Zhou, Hao Li, Lixing You, Guang-Can Guo, Wei Chen, Zheng-Fu Han. 2025-12-30. 5-GHz chip-based quantum key distribution with 1Mbps secure key rate over 150 km. https://doi.org/10.1002/lpor.202503250

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