采用两段级联单模光纤对高阶孤子脉冲进行压缩。两段光纤具有不同的反常色散值, 当高阶孤子脉冲在第一段光纤中获得最大程度压缩时, 通过转换色散值不同的光纤, 使压缩脉冲继续以高阶孤子的形式在第二段光纤中再次被压缩。每段光纤的长度都进行了优化, 使得脉冲在每段光纤中都获得最大程度的压缩。基于非线性薛定谔方程, 数值研究了初始啁啾对高阶孤子脉冲压缩的影响。研究结果表明, 初始啁啾对高阶孤子脉冲的压缩有重要影响。与无初始啁啾时的情形相比, 正的初始啁啾能增强每段光纤中脉冲的压缩效果, 降低压缩脉冲的基座能量, 而负初始啁啾的影响则相反。随着初始啁啾参量Cp的增大, 脉冲在每段光纤中的压缩因子均增加, 而基座能量、最优光纤长度均减小。

We consider the pulse compression of higher-order solitons in two cascaded single-mode fibers. The two single-mode fibers have different anomalous dispersion value. When the higher-order soliton pulse achieves maximal compression in the first fiber, by switching the fiber with different dispersion, the pulse is compressed again as a new higher-order soliton in the second fiber. Each fiber length is optimized in order to achieve maximal compression inside each fiber segment. Based on the generalized nonlinear Schrdinger equation, we numerically study the effect of initial frequency chirp on pulse compression of higher-order solitons. Our numerical results show that initial frequency chirp has significant influence on higher-order solitons pulse compression. In comparison with the case of without initial chirp, a positive chirp can enhance the pulse compression and can reduce the pedestal energy in each fiber segment, while a negative chirp does the opposite. In each fiber segment, as the chirp parameter Cp increases, the compression factor increases, while pedestal energy and optimal fiber length decrease.