色散缓变光纤中的调制不稳定性分析

Modulation Instability in Decreasing Dispersion Fibers

研究了色散缓变光纤中调制不稳定效应 ,得到了增益谱与光纤纵向色散参量的一般关系式。结果表明 ,色散缓变光纤较常规光纤具有较宽的增益谱。选取色散缓变光纤的色散参量可以获得较大的增益带宽。数值模拟显示 ,利用色散缓变光纤中的调制不稳定性可以产生高重复率的基本孤子脉冲串。

Modulation instability in decreasing dispersion fibers (DDF) is investigated by meansof theoretical analysis and numerical simulation.The gain spectrum of modulation instability is obtained as a function of axially- varying dispersion parameter.The results show thatthe gain spectrum of DDF is much broader than that of ordinary optical fibers.The broad gain bandwidth can be obtained by selecting the dispersion parameter of DDF. The numerical simulation also shows that fundamental soliton pulses with high repetition rate can be generated in this kind of fiber by modulation instability.