依据克尔透镜锁模(KLM)激光器的“厚透镜”模型,选择钛宝石激光器工作在下稳区的上边界, 采用抽运光腰略大于腔模光腰,使激光介质内腔模光斑会随腔内功率增大而增大的软光阑方式实现增益调制锁模, 减弱了增 益饱和效应和频率模尺寸效应的影响,获得了 144 nm的宽带频谱飞秒激光,并在710 nm附近获得了8.5 fs的脉 冲输出。

Base on the "thick-lens" model, the KLM Ti:sapphire laser operation point is selected near the upper edge of the HMS stable region, so that the effects of intracavity gain saturation and frequency dependent mode size are reduced. As a result, the pulse bandwidth broadening is enhanced significantly. Pulses with bandwidth of 144 nm have been generated from this laser. As short as 8. 5 fs pulses are obtained at wavelength centered at 710 nm.