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arXiv · 2505.01852

All-fiber highly efficient delivery of 2 kW laser over 2.45 km hollow-core fiber

Abstract

Anti-resonant hollow-core fibers (AR-HCFs) have emerged as an important medium for high-power laser delivery due to their low optical nonlinearity and high damage threshold. However, current delivery systems of high-power laser based on AR-HCFs mainly rely on free-space optical components, which limits long-term stability in dynamic environments. Here, we report an all-fiber delivery of 2 kW laser with 85.3% transmission efficiency over 2.45 km, using a self-fabricated AR-HCF with a record low transmission loss of 0.175 dB/km at 1080 nm. This represents a nearly 500-fold improvement in the power-distance product compared to reported all-fiber AR-HCF-based laser transmission systems, achieving a record transmission distance for high-power laser delivery. Notably, we observed the phenomenon of stimulated Raman scattering amplified within the silica nested tubes in AR-HCF for the first time. By effectively suppressing the Raman noise from the laser source, we achieve an all-fiber laser delivery without stimulated Raman scattering of silica glass. This work marks a significant breakthrough in multi-kilometer and multi-kilowatt power delivery that is potentially useful for industrial manufacturing, nuclear decommissioning, laser drilling of oil, particle acceleration and so on.

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Jing Shi, Binyu Rao, Zilun Chen, Zefeng Wang, Guangrong Sun, Zuyin Xu, Zhen Huang, Peng Li, Zihan Dong, Min Fu, Xin Tian, Baolai Yang, Jian Zhang, Zhiyue Zhou, Tianyu Li, Lei Zhang, Biao Shui, Chenxin Gao, Jinbao Chen. 2025-05-03. All-fiber highly efficient delivery of 2 kW laser over 2.45 km hollow-core fiber. https://arxiv.org/abs/2505.01852

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