[1] Zervas M N, Codemard C A. High power fiber lasers: a review[J]. IEEE Journal of Selected Topics in Quantum Electronics, 20, 0904123(2014).

[2] Zhou Pu, Leng Jinyong, Xiao Hu, . High average power fiber lasers: research progress and future prospect[J]. Chinese Journal of Lasers, 48, 2000001(2021).

[3] Li Fengyun, Li Yue, Song Huaqing, . Homemade fiber enables 20.88 kW laser output with high SRS suppression ratio[J]. Chinese Journal of Lasers, 48, 2116002(2021).

[4] Lin Aoxiang, Xiao Qirong, Ni Li, . Homemade YDF active fiber realizes 20 kW laser output[J]. Chinese Journal of Lasers, 48, 0916003(2021).

[5] Chen Xiaolong, He Yu, Xu Zhongwei, . Theoretical and experimental investigation of a 10-kW high-efficiency 1070-nm fiber amplifier[J]. Chinese Journal of Lasers, 47, 1006001(2020).

[6] [6] Ikoma S, Nguyen H K, Kashiwagi M, et al. 3 kW single stage allfiber Ybdoped singlemode fiber laser f highly reflective highly thermal conductive materials processing[C]Proceedings of SPIE 10083, Fiber Lasers XIV: Technology Systems. 2017: 100830Y.

[7] [7] Seah C P, Lim W Y W, Chua S L. A 4kW fiber amplifier with good beam quality employing confineddoped gain fiber[C]Advanced Solid State Lasers 2018. 2018: AM2A. 2.

[8] Zhang Zhilun, Zhang Fangfang, Lin Xianfeng, . Home-made confined-doped fiber with 3-kW all-fiber laser oscillating output[J]. Acta Physica Sinica, 69, 234205(2020).

[9] [9] Wang Biao, Pang Lu, Liu Jun. Single mode 2.4kW partdoped ytterbium fiber fabricated by modified chemical vap deposition technique[C]Proceedings of SPIE 11427, Second Target Recognition Artificial Intelligence Summit Fum. 2020: 114271X.

[10] Huang Zhimeng, Shu Qiang, Luo Yun, et al. 3.5 kW narrow-linewidth monolithic fiber amplifier at 1064 nm by employing a confined doping fiber[J]. Journal of the Optical Society of America B, 38, 2945-2952(2021).

[11] Wu Hanshuo, An Yi, Xiao Hu, . Homemade confined-doped fiber enables 7 kW laser output with good beam quality[J]. Chinese Journal of Lasers, 48, 2416002(2021).

[12] Wu Hanshuo, Li Ruixian, Xiao Hu, et al. First demonstration of a bidirectional tandem-pumped high-brightness 8 kW level confined-doped fiber amplifier[J]. Journal of Lightwave Technology, 40, 5673-5681(2022).