飞秒光脉冲在光子晶体光纤中的非线性传输和超连续谱产生

采用分步傅里叶方法数值模拟了飞秒光脉冲在光子晶体光纤中非线性传输和超连续谱的产生. 计算和分析了高阶色散和非线性效应对超连续谱形状和带宽的影响. 结果表明在光子晶体光纤中产生了孤子自频移现象. 同时也发现脉冲内拉曼散射和自相位调制的联合作用导致了超连续谱中精细结构的出现. 另外，还发现高阶色散和初始光脉冲的峰值功率对超连续谱的带宽和平滑也有直接影响. 关键词： 光子晶体光纤 孤子自频移 超连续谱

Nonlinear propagation and supercontinuum generation of a femtosecond pulse in photonic crystal fibers

A theoretical investigation with the method of split-step Fourier is presented on the nonlinear propagation and supercontinuum generation of a femtosecond laser pulse in a photonic crystal fiber. The impact of high-order dispersion and nonlinear effects on spectral shape and band width is simulated and analyzed. It is found that soliton self-frequency shift is generated in a photonic crystal fiber. It is also found that intrapulse stimulated Raman scattering and self-phase modulation result in the fine spectral substructure of the supercontinnum. The band width and smoothing of the supercontinuum are found to be related to the higher-order dispersion and the power of the initial laser pulse.