高功率光纤激光器喇曼效应的数值分析

为了研究掺镱双包层高功率光纤激光器的结构参量对喇曼效应的影响,利用数值模拟方法求解有关抽运光、激光和斯托克斯波的稳态速率方程组,得到了激光和斯托克斯波在光纤轴向的分布特性,以及喇曼阈值抽运功率与光纤激光器结构参量的关系.结果表明,当光纤激光器采用大模面积、短腔长、小斯托克斯波辐射截面和长激光波长的结构参量时,能显著提高喇曼阈值抽运功率,降低喇曼效应.

Numerical analysis of Raman effects in high power fiber laser

Based on the numerical simulation method for solving the steady-state rate equations that describe the pump,laser and Stokes waves,the dependence of Raman effects on the parameter of high power Yb3 -doped double-clad fiber laser was investigated.The distribution of laser power and Stokes power along the fiber,and the relation between the threshold pump power for the generation of the stimulated Raman scattering(SRS) and the parameter of fiber laser were obtained.Numerical results show that the threshold pump power for the generation of SRS can be improved,and the Raman effects can be effectively suppressed by using large mode area fiber,shortening the cavity length,reducing the emission cross-section of Yb3 at the Stokes wavelength and adopting a longer lasing wavelength.