负啁啾高强度飞秒脉冲在正常色散材料中传输特性研究

Properties of the propagation of negatively chirped femtosecond pulses in normally dispersive media

利用块状正常色散材料作非线性介质,实验研究了负啁啾强激光飞秒脉冲在正常色散材料的传输过程中,脉冲波形及频谱随入射脉冲能量的变化特性.实验发现,负啁啾脉冲经过材料后激光光谱在被整形和压缩的同时,脉冲宽度也被压缩.实验获得的压缩脉冲宽度短于相等光谱宽度下的双曲正割转换极限脉冲宽度.数值模拟结果显示,在实验条件下模拟结果具有同样的变化特性.

We experimentally studied the temporal and spectral characteristics of the output pulses after the negatively chirped pulses passed through normally dispersive media. The spectrum of the pulse is narrowed and reshaped due to strong self-actions. The pulse is self-compressed, instead of broadening, accompanied with the spectrum narrowing in the experiment. For the same spectral bandwidth, shorter than sech^2 transform-limited self-compressed femtoseeond pulses are obtained. The simulation result is in agreement with the experiment.