The numerical results show that the self-frequency shift and self-steepening make the pulse drift backward nonlinearly,and the drift of the former pulse smaller than that of the latter.

• 数值结果表明:自频移和自陡峭都使脉冲向后沿呈现非线性的偏移,前一个脉冲的偏移量很小,基本上是呈线性偏移,后一个脉冲随传输距离的增加,偏移量逐渐的增大,呈非线性偏移。