色散缓变光纤耦合器中的调制不稳定性  

Modulation Instability of Dispersion Decreasing Fiber Couplers

作　　者：周彦勇[1] 贾维国[1] 迎春[1,2] 包红梅[1] 

机构地区：[1]内蒙古大学物理系,呼和浩特010021 [2]内蒙古工业大学,呼和浩特010062

出　　处：《光子学报》2008年第10期1952-1957,共6页Acta Photonica Sinica

基　　金：国家自然科学基金(60468001)资助

摘　　要：用奇偶超模对光纤耦合器的耦合模方程重写.讨论了当输入条件使奇偶超模其中之一被单独激发时,色散缓变光纤耦合器中的调制不稳定性,结合调制不稳定性,分析了色散缓变光纤耦合器在准连续波条件下的非线性效应.结果表明:在正常和反常色散区存在新型调制不稳定性.当满足一定条件时,在色散缓变光纤耦合器中传播的准连续波光束可以分解成脉冲序列,并且脉冲几乎不展宽,由此可以分离和提取稳定的超短脉冲;当输入功率一定时,增益谱随着传输距离的改变,形态基本保持不变;当传输距离一定时,增益谱随着输入功率的增强,宽度变宽,强度增强.The nonlinear coupled-mode equanons were rewritten by even and odd modes. The modulation instability Of dispersion decreasing fiber coupler was studiedwhen either even or odd mode is launched alone and its nonlinearity combined with modulation instability by using relatively long iquasi-cw） pulses was analyzed. The result shows that there are new types of modulation instability in both the normal and the anomalous-dispersion regimes. Quasi-cw can be changed into pulse array with certain conditions, it can extract super short pulses from this. And. the shape of gain spectra is invariable as function of propagation distance when input power is constant. The bandwidth of gain spectra widens and itrs strength heightens as alteration of input power when propagation distance is constant.

关 键 词：色散缓变光纤耦合器 奇次超模 偶次超模 调制不稳定性 

分 类 号：TN253[电子电信—物理电子学]