Mete Busra, Yeniay Aydın, Ecevit F Necati, Kalyoncu Salih K
Appl Opt. 2022 Dec 1;61(34):10121-10125. doi: 10.1364/AO.479366.
An in-band pumping technique that employs low numerical aperture (NA) and high brightness fiber lasers emitting at 1018 nm enables outstanding power scaling performance by increasing pump power handling capacity of fiber components, reducing thermal load and quantum defect. Here, we present design criteria for an in-band pumped fiber master oscillator power amplifier (MOPA) structure, pumped with 1018 nm fiber lasers, as well as mitigation strategies for nonlinear effects for scalable single-mode laser operation at multi-kilowatt power levels. In addition, we report experimental demonstration of an in-band pumped MOPA with an output power scaling up to 4.63 kW and a slope efficiency of ∼88. The MOPA system is pumped by 18×264 high brightness fiber lasers operating at 1017.8±0.3 with an NA of <0.075. The laser emits at 1080.4 nm wavelength with a stimulated Raman scattering suppression of >36.8 and has a near-diffraction-limited beam quality of ∼1.61. To the best of our knowledge, our laser has the highest brightness of 153 ⋅ ⋅ reported at 1080 nm in co-pumping configuration.
一种采用低数值孔径（NA）和发射波长为1018nm的高亮度光纤激光器的带内泵浦技术，通过提高光纤组件的泵浦功率处理能力、降低热负载和量子缺陷，实现了出色的功率缩放性能。在此，我们提出了一种由1018nm光纤激光器泵浦的带内泵浦光纤主振荡功率放大器（MOPA）结构的设计标准，以及在多千瓦功率水平下实现可扩展单模激光运行的非线性效应缓解策略。此外，我们报告了一种带内泵浦MOPA的实验演示，其输出功率缩放至4.63kW，斜率效率约为88%。该MOPA系统由18×264个高亮度光纤激光器泵浦，这些激光器工作在1017.8±0.3nm，NA<0.075。该激光器在1080.4nm波长处发射，受激拉曼散射抑制>36.8dB，具有约1.61的近衍射极限光束质量。据我们所知，我们的激光器在共泵浦配置下在1080nm处具有报道的最高亮度153W/(cm²·sr)。
