论文部分内容阅读
利用激光脉冲在光纤光栅中传播时所遵守的相干耦合非线性薛定谔方程,研究了激光脉冲在局部高斯变迹布拉格光纤光栅中传输时,在反常色散区和正常色散区所产生的调制不稳定性。结果表明在反常色散区和正常色散区都能产生调制不稳定性;在反常色散区,当输入功率达到一定数值、传输距离一定时,当f=-1禁带之上能带底时,调制不稳定性增益的强度最强、宽度最窄;当远离能带底时强度减弱、宽度变宽;在正常色散区,在产生调制不稳定性功率区域,调制不稳定性存在并从给定值一直持续到无穷;并且,在反常色散区和在正常色散区,增益谱都受到局部高斯变迹函数的制约。
The coherent coupled nonlinear Schrödinger equation, which is observed when the laser pulse propagates in a fiber grating, is used to study the modulation instability caused by the laser pulses in the anomalous dispersion region and the normal dispersion region when they are transmitted in the local Gaussian apodized Bragg grating. . The results show that modulation instability can occur in both the anomalous and normal dispersion regions. In the anomalous dispersion region, when the input power reaches a certain value and the transmission distance is constant, when f = -1, Unstable gain has the strongest intensity and the narrowest width; the strength decreases and the width becomes wider when away from the end of the energy band; in the normal dispersion region, the modulation instability exists in the region where the modulation instability occurs, and from the given value Continues until infinity; and, in both the anomalous dispersion region and the normal dispersion region, the gain spectrum is constrained by the local Gaussian apodization function.