结合双包层掺镱光纤(YDCF)和主振荡功率放大(MOPA)技术,利用熔融拉锥的光纤侧面耦合器,设计和实验研究了全光纤结构的脉冲光纤放大器。在不同重复频率时,通过放大脉冲激光的输出光谱,对输出脉冲激光中的剩余抽运光和受激拉曼散射光功率进行了修正;并研究了激光脉冲的时域特性,以及在脉冲放大过程中对输出激光脉冲宽度的压缩作用。获得输出放大脉冲激光的主要参数：峰值波长为1075 nm,脉冲宽度为18～300 ns,重复频率为5～20 kHz,峰值功率达9.87 kW,斜率效率达52.2%,光束质量M2=2.0。同时,制作完成了一台结构紧凑、全光纤结构的脉冲光纤放大器样机,其最大外形尺寸为370 mm×270 mm×90 mm。

Using the side-pumped coupler made from fused tapered fiber, the Yb-doped double-cladding fiber (YDCF) master oscillation power amplification (MOPA) with all-fiber structure is experimentally studied. At different repetition frequency, the residual pump power and the stimulated Raman scattering light power in the output pulse laser have been corrected by the amplified output spectrum, and the temporal characteristic of laser pulse power is analyzed, and the pulse duration is compressed while the pulse laser is amplified. From the experiments, the output pulse laser is obtained with peak wavelength of 1075 nm, pulse duration of 18～300 ns, repetition frequency of 5～20 kHz, peak power of 9.87 kW, slope efficiency of 52.2%, and beam quality M2=2.0. A compact prototype of the all-fiber pulse fiber amplifier has been finished, and the maximum dimension is 370 mm×270 mm×90 mm.