亚10 fs激光脉冲产生中的受激拉曼散射与四波混频效应

自行搭建的自锁模钛宝石激光器工作在下稳区的上边界附近，采用熔融石英棱镜对在激光器谐振腔的腔内和腔外同时进行群速度色散补偿.随着腔内棱镜对提供色散补偿的变化，输出激光脉冲的频谱会突然展宽至664—840nm，其空间模式也由基横模变化至衍射环状结构，这是受激拉曼散射和四波混频效应导致锁模激光脉冲频谱进一步展宽的结果.在此状态下自锁模钛宝石激光器可实现670—865nm范围的波长调谐.如此宽的频谱为钛宝石激光器产生亚10fs激光脉冲提供了必要的条件. 关键词： 飞秒激光脉冲 受激拉曼散射 四波混频 群速度色散

The stimulated Raman scattering and the four wave mixing in the generation of sub-10 fs pulses

A self-built self-mode-locked Ti:sapphire laser is operated at the upper edge of the stable region. Tow double-prism systems are used to compensate for thesecond-order dispersion in and out of the laser cavity. Broad band laser pulses with bandwidth of 664—840nm have been generated, and their mode changes from the basic mode to the ring structure. The interesting experimental phenomenon is due to the stimulated Raman scattering and the four wave mixing, which provides the necessary condition to generate the sub-10fs laser pulses.