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arXiv · 2510.11086

Efficient and Robust Spatial-to-Fiber Coupling forMultimode Quantum Networks via CascadedAdaptive Feedback Control

Ya Li·WanRu Wang·Weizhe Qiao·Qizhou Wu·Changqing Niu·Xiaolong Zou·Youxing Chen·Xin Guo
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Abstract

Duan-Lukin-Cirac-Zoller (DLCZ)-based multimodequantum networks rely on efficient spatial-to-fiber coupling, yetenvironmental perturbations compromise this performance. Wedevelop a cascaded adaptive feedback control system integratedinto the quantum entanglement source preparation path.Leveraging a power-feedback hillclimbing algorithm, itdynamically regulates piezoelectric-actuated mirrors to achieveautonomous multi-dimensional beam alignment, Experimentsshow it rapidly boosts single-mode fiber (SMF) coupling efficieneyto over 70% within 20 seconds and entering the most efficient andstable transmission state after 75 seconds.Importantly, it enhancesthe stability of the atom-photon interfacecritical for quantumlight-matter interactionsproviding a practical framework forefficient, robust spatial light transmission in scalable quantumnetworks.

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Ya Li, WanRu Wang, Weizhe Qiao, Qizhou Wu, Changqing Niu, Xiaolong Zou, Youxing Chen, Xin Guo. 2025-10-13. Efficient and Robust Spatial-to-Fiber Coupling forMultimode Quantum Networks via CascadedAdaptive Feedback Control. https://arxiv.org/abs/2510.11086

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