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arXiv · 2309.00221

A multinode quantum network over a metropolitan area

Jian-Long Liu·Xi-Yu Luo·Yong Yu·Chao-Yang Wang·Bin Wang·Yi Hu·Jun Li·Ming-Yang Zheng·Bo Yao·Zi Yan·Da Teng·Jin-Wei Jiang·Xiao-Bing Liu·Xiu-Ping Xie·Jun Zhang·Qing-He Mao·Xiao Jiang·Qiang Zhang·Xiao-Hui Bao·Jian-Wei Pan
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Abstract

Towards realizing the future quantum internet, a pivotal milestone entails the transition from two-node proof-of-principle experiments conducted in laboratories to comprehensive, multi-node setups on large scales. Here, we report on the debut implementation of a multi-node entanglement-based quantum network over a metropolitan area. We equipped three quantum nodes with atomic quantum memories and their telecom interfaces, and combined them into a scalable phase-stabilized architecture through a server node. We demonstrated heralded entanglement generation between two quantum nodes situated 12.5 km apart, and the storage of entanglement exceeding the round-trip communication time. We also showed the concurrent entanglement generation on three links. Our work provides a metropolitan-scale testbed for the evaluation and exploration of multi-node quantum network protocols and starts a new stage of quantum internet research.

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Jian-Long Liu, Xi-Yu Luo, Yong Yu, Chao-Yang Wang, Bin Wang, Yi Hu, Jun Li, Ming-Yang Zheng, Bo Yao, Zi Yan, Da Teng, Jin-Wei Jiang, Xiao-Bing Liu, Xiu-Ping Xie, Jun Zhang, Qing-He Mao, Xiao Jiang, Qiang Zhang, Xiao-Hui Bao, Jian-Wei Pan. 2023-09-01. A multinode quantum network over a metropolitan area. https://doi.org/10.1038/s41586-024-07308-0

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