受激布里渊散射介质CCl4中脉冲传输与功率限幅特性

分析了受激布里渊散射介质CCl4对纳秒激光脉冲的传输特性及功率限幅特性. 结果表明：透射脉冲波形随抽运光能量增加而压缩变形，脉冲前沿保持高斯型，后沿被压缩成功率“平台”，功率“平台”随抽运脉冲能量增加而逐渐变宽，但功率水平不变，表明该光学系统具有的功率限幅特性. 详细分析了功率限幅特性随抽运能量的变化规律和时间响应特性规律，采用脉宽为10ns、波长为1.06μm的Nd:YAG激光脉冲进行实验验证，理论与实验结论相符合.  关键词： 受激布里渊散射 功率限幅

Nonlinear propagation and power limiting of nanosecond laser pulse by stimulated Brillouin scattering in CCl4

Based on the quasi-steady stimulated Brillouin scattering theory, the nonlinear propagation of 1.064μm, YAG nanosecond pulsed light was analyzed numerically and treated with a theoretical model that includes the spontaneous nature of the initiation of stimulated Brillouin scattering(SBS). Then the pulse propagation and power limiting effects (including both power limiting and energy limiting) were obtained in the SBS process. The temporal pulse reshaping and power limiting have been given graphically on SBS mechanism with a nonlinear medium CCl4 for various pump energies and pulse-width (10ns). The power transmission properties and delay time of the power limiting effect depending on pump energy were given theoretically. And the influence of pump energy on the transmitted pulse profiles and delay time were investigated experimentally. The numerical simulations of transmitted pulse characteristics were in good agreement with the experimental results.