前向拉曼兼容光纤激光器的优化设计

Optimization Design of Forward Raman Compatible Fiber Lasers

高功率全光纤结构激光系统中，后向受激拉曼散射光会被合束器等器件吸收，产生热量并对器件造成破坏，成为限制功率提升的因素之一。提出前向拉曼兼容光纤激光器概念，通过注入辅助种子光抑制后向光来提高输出功率。建立了含有受激拉曼散射效应（SRS）的主振荡功率放大（MOPA）结构数值模型，模拟分析了后向光的特性，且比较了注入不同功率、不同波长辅助种子光对输出总功率的影响。计算结果表明，当注入辅助种子光在特定波长特定功率时，系统输出功率可提升一倍以上。

In high power all fiber laser systems, the backward stimulated Raman Stokes light will be absorbed in combiners and converted into heat finally, which can cause damage to devices and restrain output power. Forward Raman compatible fiber laser concept is put forward to suppress the backward Raman Stokes light by injecting an auxiliary seed. The model of master oscillator power amplifier （MOPA） with stimulated Raman scattering （SRS） effect is simulated and the characteristics of backward Raman Stokes light are discussed. The effects of different auxiliary seeds injections on the increase of output power are compared. Results of simulations have illustrated that the output power of the system can be increased by more than one time when the certain power and wavelength auxiliary seed are injected.