双包层掺铥光纤放大器中的受激布里渊散射  

Stimulated brillouin scattering in double-clad thulium-doped fiber amplifier

作　　者：刘庆敏 孙慧杰 侯尚林 雷景丽[2] 武刚[2] 晏祖勇[2] LIU Qing-min;SUN Hui-jie;HOU Shang-lin;LEI Jing-li;WU Gang;YAN Zu-yong(College of Electrical and Information Engineering,Lanzhou University of Technology,Lanzhou 730050,China;School of Science,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学电气工程与信息工程学院,甘肃兰州730050 [2]兰州理工大学理学院,甘肃兰州730050

出　　处：《中国光学（中英文）》2024年第1期226-237,共12页Chinese Optics

基　　金：国家自然科学基金(No.61665005);兰州理工大学红柳一流学科发展计划资助项目。

摘　　要：理论分析了波长为2μm的掺铥光纤放大器中受激布里渊散射(SBS)对激光输出性能的影响,研究了双包层掺铥光纤在793 nm的泵浦波长和1.9~2.1μm的激光工作波段的光模分布、有效折射率、有效模场面积和归一化频率,数值计算了在1.9~2.1μm的激光工作波段双包层掺铥光纤中的布里渊频移和布里渊增益谱等SBS特性。利用增益光纤中的受激布里渊散射理论模型,研究了受激布里渊散射对掺铥光纤放大器激光输出性能的影响。在DTDF-10/130双包层掺铥光纤中,使用功率为100 W、波长为793 nm的连续光作为泵浦,可对波长为2μm、功率为0.01 W的连续信号光进行放大。当泵浦光功率填充因子为0.01、0.02和0.03时,信号光的最大输出功率分别为25.27 W、31.08 W和34.06 W。对应的最佳双包层光纤长度为2.66 m、2.02 m和1.75 m,由受激布里渊散射产生的斯托克斯光功率分别为1.68 W、1.39 W和1.14 W。结果表明,在掺铥光纤放大器中使用泵浦光功率填充因子大的双包层光纤可以降低光纤长度,从而减小受激布里渊散射对信号激光输出功率的影响。本文的数值模型可以对光纤放大器的光纤长度进行优化,对提高实验效率、降低实验成本具有重要价值。In this paper,the effect of Stimulated Brillouin Scattering(SBS)on the laser output performance in a 2μm thulium-doped fiber amplifier was analyzed theoretically.The optical mode distribution,the effective refractive index,the effective mode field area,and the normalized frequency of the double-clad thuliumdoped fiber at 793 nm pump wavelength and 1.9−2.1μm laser waveband were studied.The stimulated Brillouin scattering characteristics,including the Brillouin frequency shift and the Brillouin gain spectrum,in the double-clad thulium-doped fiber were numerically simulated in the laser waveband of 1.9−2.1μm.The influence of stimulated Brillouin scattering on the laser output performance of thulium-doped fiber amplifiers was investigated using the theoretical model of stimulated Brillouin scattering in gain fibers.In the DTDF-10/130 double-clad thulium-doped fiber,a continuous wave with power of 100 W and wavelength of 793 nm is used as a pump to amplify a continuous signal wave with wavelength of 2μm and power of 0.01 W.The maximum output powers of the signal wave are 25.27 W,31.08 W and 34.06 W when the pump power filling factors are 0.01,0.02 and 0.03,respectively.The corresponding optimal double-clad fiber lengths are 2.66 m,2.02 m and 1.75 m.Additionally,the Stokes optical powers generated by the stimulated Brillouin scattering are 1.68 W,1.39 W and 1.14 W,respectively.The results show that the double-clad fiber with large pump power filling factor in the thulium-doped fiber amplifier can effectively reduce the fiber length,thus to minimize the influence of stimulated Brillouin scattering on the output power of the signal laser.The numerical model can optimize the fiber length of the fiber amplifier,which is of great significance to improve experimental efficiency and reduce experimental costs.

关 键 词：受激布里渊散射 双包层 掺铥光纤 放大器 

分 类 号：O437.2[机械工程—光学工程]