全光纤结构的两级分布式窄线宽双包层光纤放大器

Dual-Stages All-Fiber Narrow-Linewidth Fiber Amplifier

利用主振荡功率放大(MOPA)技术,实验研究了两级级联、全光纤结构的窄线宽连续激光放大器。其中,以20dB光谱线宽0.078nm的窄线光纤激光器为信号光源,两个放大级中分别采用光纤侧面耦合器,(6+1)×1光纤合束器实现抽运光功率的耦合,以及使用1053nm单模纤芯的双包层掺镱光纤、大模场面积的掺镱双包层光纤作为增益光纤。在全光纤结构放大器中,对第二级放大级中(6+1)×1抽运光注入端的反向传输光的光谱和功率进行了监测和分析。通过优化增益光纤的长度,抑制了掺镱光纤中自发辐射光的自生激光振荡。在窄线宽激光放大过程中实现了中心波长1053 nm,总放大增益27.6 dB,功率16.09 W的稳定激光输出,没有发现受激布里渊散射和受激拉曼散射等非线性效应。

Using the master oscillation power amplification (MOPA) technology, the dual-stages narrow linewidth fiber amplifier with all-fiber structure is experimentally studied. In the fiber amplifier, the narrow linewidth fiber laser with 20 dB spectral width of 0.078 nm is used as the seeding signal, and the side pumped coupler that is made from the fused tapered fiber, and the (6+1) × 1 multimode fiber combiner are used as the pump power coupling components, and the Yb-doped double cladding fiber with single mode core in the wavelength of 1053 nm, the large mode area Yb-doped double cladding fiber are used as the gain fibers in the two fiber stages, respectively. In the second fiber amplification stage, the back propagation light in the pump input end of the (6+1) × 1 multimode fiber combiner is monitored and analyzed, which are including the spectra component and the light power. In order to suppress the spurious lasing of the amplification stimulation emission light, the length of the gain fiber is optimized experimentally. At last, the characters of the stable amplification output laser are the peak wavelength 1053 nm, total gain 27.6 dB, output power 16.09 W, and the nonlinear effects are not observed.