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arXiv · 2606.18840

Field Demonstration of a Multi-User Continuous-Variable Quantum Access Network for Quantum-to-the-Home

Junpeng Zhang·Xu Liu·Qijun Zhang·Yifeng Liang·Yue Yu·Peng Huang·Huasheng Li·Yingming Zhou·Jingyu Yang·Chunchen Li·Yunfan Chen·Cheng Zheng·Ciqing Deng·Tao Wang·Guihua Zeng
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Abstract

Realizing scalable Quantum-to-the-Home (QTTH) faces a bottleneck: link asymmetry in broadcast continuous-variable quantum access networks (CV-QANs) hinders the selection of a globally optimal modulation variance. We demonstrate a downstream broadcast CV-QAN connecting a Quantum Line Terminal (QLT) to multiple Quantum Network Units (QNUs) over commercial fiber. Operating within a trusted local network domain, we establish a multi-user utility model to select the optimal shared variance, balancing network efficiency and user fairness. Supported by robust digital signal processing, our 1:16 field trial achieves Mbit/s-level asymptotic secure key rates, bridging theoretical protocols with Fiber-to-the-Home reality and guiding future scalable access architectures.

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Junpeng Zhang, Xu Liu, Qijun Zhang, Yifeng Liang, Yue Yu, Peng Huang, Huasheng Li, Yingming Zhou, Jingyu Yang, Chunchen Li, Yunfan Chen, Cheng Zheng, Ciqing Deng, Tao Wang, Guihua Zeng. 2026-06-17. Field Demonstration of a Multi-User Continuous-Variable Quantum Access Network for Quantum-to-the-Home. https://arxiv.org/abs/2606.18840

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