双零色散点光子晶体光纤中红移辐射的产生

为了研究双零色散点光子晶体光纤反常色散区中红移辐射的产生,采用分步傅里叶方法数值模拟了飞秒脉冲在双零色散点光子晶体光纤反常色散区中的非线性传输和红移辐射的产生。分析了抽运脉冲的脉宽、抽运波长、入射峰值功率对红移辐射的影响。结果表明,当超短脉冲靠近第2个零色散点的反常色散区进行抽运时,喇曼孤子受高阶色散效应的影响产生了红移辐射现象;当增大抽运激光的入射峰值功率或增大脉宽时,红移辐射均增强,而且发生了明显的分裂现象,其起因可归结于喇曼孤子和红移辐射之间的交叉相位调制;此外,3阶色散效应对红移辐射也有重要的影响,当增大3阶色散系数时,红移辐射可得到进一步加强。

Red-shifted radiation generation in a photonic crystal fiber with two zero dispersion wavelengths

In order to study the red-shifted radiation generation in a photonic crystal fiber with two zero dispersion wavelengths in the anomalous dispersion region,the nonlinear propagation and red-shifted radiation generation of a femtosecond laser pulse in a photonic crystal fiber were simulated with the split-step Fourier algorithm.The effect of pulse width,center wavelength and input peak power of the pump pulse on the red-shifted radiation was analyzed.It is found the phenomenon of red-shifted radiation of Raman soliton caused by higher-order dispersion occurs when the pump wavelength is located in the anomalous dispersion region nearby the second zero dispersion wavelength.The intensity of red-shifted radiation components can be enhanced with the input peak power or pulse width increased.In addition,the three-order dispersion effect also has an important effect on the red-shifted radiation.The intensity of red-shifted radiation components can be further enhanced by increasing the three-order dispersion coefficient.