中文摘要：

从非线性薛定谔方程出发，利用分步傅里叶方法，研究了时空耦合飞秒脉冲在熔石英玻璃中传输时，传输距离、入射激光脉冲峰值功率、衍射、色散和非线性等因素对超连续谱产生的影响。结果表明，飞秒脉冲在熔石英玻璃中传输时，超连续谱的产生主要分为两阶段：由材料的自聚焦等三阶非线性效应引起的脉冲压缩阶段及由自相位调制和材料群速度色散引起脉冲分裂阶段。当高峰值功率的飞秒脉冲在熔石英玻璃中传输时，材料的三阶非线性效应抑制衍射效应，引起脉冲压缩，从而产生子脉冲，由此引入新的频率成分。同时，还研究了同一脉冲不同横向空间位置处的超连续谱的变化规律，在中心频率两侧均有新频率产生。最后，通过实验证实了超连续谱的产生。

英文摘要：

Starting from Nonlinear Schrodinger＇s equation and using the split-step Fourier method, the authors studied the characters of the supereontinuum generation of femtoseeond laser pulse propagating in fused silica, and many physical factors were included such as propagation distance, input pulse peak power, diffraction effect, dispersion effect andnonlinear effect etc. The results show that when the femtosecond pulse propagated inside the fused silica, the process of supercontinuum generation could be divided into two main stages： the pulse compression stage, which was induced by the self-focus and other third nonlinear effects of the fused silica; and the pulse split stage, which was caused by the self-phase modulation and the group velocity dispersion of the fused silica. When the femtosecond pulse propagated inside the fused silica with high input peak power, the 3rd-order nonlinear effect of material induced pulse compression and then the subpulses were produced, so that new frequency components were introduced. At the same time, the authors also studied the spectral distribution of the pulse at different spacial locations, and there are new frequencies around the central frequency. Finally, some experiments were done to demonstrate the supercontinuum generation.