自锁模钛宝石激光器中的光谱调制和双脉冲运转

 在自锁模钛宝石激光器中，除可形成传统的单脉冲外，在适当的条件下，还可产生双脉冲。本文运用广义脉宽公式单独计及棱镜系统的色散，用分步富氏法数值求解非线性薛定谔方程，在脉宽自洽的判据下，模拟了双脉冲的形成过程。结果表明，小量的净负色散配合强的啁啾是形成光谱调制的条件。双脉冲只产生在有限的参数范围内且极易被破坏。

Spectral modulation and double-pulse formation in Kerr-lens modelocked Ti:sapphire laser

Besides the conventional single pulse train generation, the Ti:sapphire laser system sometimes produces two or even more pulses should proper conditions be satisfied. By treating the pulse propagation within the laser gain medium with the help of split step Fourier method, independently taking into account of the dispersion originating from the prism sequence, and making use of a generalized pulsewidth formula, the double pulse formation process is numerically simulated in a self consistent scheme. It is revealed that the condition of a tiny net negative dispersion with strong chirp is mandatory. The double pulse generation manifests itself in a narrow range of physical parameters, thereby pose it as a metastable state.