自陡对光纤耦合器调制不稳定性的影响

当考虑自陡效应时,从光纤耦合器的耦合模方程出发,用偶奇超模对其进行了重写。讨论了当输入条件使奇偶超模的其中之一被单独激发时光纤耦合器中的自陡效应对调制不稳定性的影响。结果表明:在光纤耦合器中不论是正常色散区还是反常色散区,当输入功率一定时,随着自陡参数的增大,调制不稳定性增益谱较多地显示出了强度变弱和宽度变窄,最终导致光纤耦合器的超模发生畸变。

Self-steepening on modulation instability of fiber couplers

The nonlinear coupled-mode equations are rewritten by even and odd modes when there are the self-steepening effect. The effect of self-steepening on modulation instability of fiber coupler is studied,when either even or odd mode is launched alone. The result shows that there are new types of modulation instability in both the normal and the anomalous-dispersion regimes.. Furthermore,the bandwidth of modulation instability gain spectra is narrowed and the strength is weaken leads as augment of self-steepening parameter when input power is constant. The finally it leads to even and odd array eigenmodes aberrance in fiber coupler.