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arXiv · 2512.17318

Microcomb-driven large-scale fully connected quantum network

Fang-Xiang Wang·Sheng-Teng Zheng·Long Huang·Guo-We Zhang·Guang-Shu Wang·Wen-Jing Ding·Ze-Hao Wang·Shuang Wang·Zhen-Qiang Yin·Chang-Ling Zou·Brent E. Little·Guochao Wang·Lingxiao Zhu·Guang-Can Guo·Weiqiang Wang·Wenfu Zhang·Wei Chen·Zheng-Fu Han
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Abstract

Fully connected quantum networks enable simultaneously connecting every user to every other user and are the most versatile and robust networking architecture. However, the scalability of such networks remains great challenge for practical applications. Here we construct a large-scale fully connected quantum network founded on two-photon Hong-Ou-Mandel (HOM) interference, where user-to-user security is guaranteed even with untrusted network provider. Using integrated soliton microcomb (SMC) and photonic encoding chips, we realize precise massive parallel frequency generation and locking, high-visibility HOM interferences and measurement-device-independent (MDI) quantum key distribution. The proposed architecture enables a 200-user fully connected quantum network over 200 kilometers with strict information-theoretic security via untrusted network provider. The implemented networking architecture paves the way for realizing large-scale fully connected MDI quantum networks across metropolitan and intercity regions.

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Fang-Xiang Wang, Sheng-Teng Zheng, Long Huang, Guo-We Zhang, Guang-Shu Wang, Wen-Jing Ding, Ze-Hao Wang, Shuang Wang, Zhen-Qiang Yin, Chang-Ling Zou, Brent E. Little, Guochao Wang, Lingxiao Zhu, Guang-Can Guo, Weiqiang Wang, Wenfu Zhang, Wei Chen, Zheng-Fu Han. 2025-12-19. Microcomb-driven large-scale fully connected quantum network. https://doi.org/10.1038/s41467-026-75658-6

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