【摘要】 研究了色散缓变光纤中基于交叉相位调制的不稳定性,得到了同时计及离散和光纤损耗效应时的色散关系式。发现在抽运功率、传输距离、光纤损耗相同的条件下,色散缓变光纤较常规光纤具有较宽的增益谱;研究同时发现,较大的色散缓变参量及两光束较小的离散均会使增益谱的谱宽加宽,振幅的增长速度加快。并用数值方法验证了利用色散缓变光纤更易产生超短脉冲。更多还原

【Abstract】 Modulation instability induced by cross-phase modulation in decreasing dispersion fiber(DDF) is investigated.The expression of the dispersion relation is obtained when the fiber loss and the walk-off effect are taken into account.It is found that the gain spectrum of DDF is much broader than that of ordinary optical fibers when the pump power,the propagation distance and the fiber loss are the same with the ones in ordinary optical fibers,respectively.It is also found that using a DDF with a greater dispersion parameter,or using a smaller walk-off effect can broaden the gain spectrum width and increase the maximum value of gain spectrum.The simulation also shows that ultrashort pulses can be easily generated in this kind of fiber by the modulation instability.更多还原