微结构光纤中超短激光脉冲传输的数值模拟

在传统求解广义非线性薛定谔方程(GNSE)分步傅里叶方法的基础上，提出了利用自适应分步 傅里叶方法(ASSFM)求解GNSE.数值模拟发现：在发生显著孤子峰值频移且微结构光纤的色散 和非线性参数随频率显著变化的情况下，采用ASSFM对超短脉冲在光纤中传输进行模拟是很 必要的，微结构光纤色散特性对超短脉冲在微结构光纤中的演化以及超连续光谱展宽有很大 影响.ASSFM可以合理地考虑到微结构光纤特性参数随脉冲演化过程中峰值功率所对应波长（ 或频率）的变化，从而更精确地模拟超短脉冲在微结构光纤中的传输. 关键词： 微结构光纤 超短脉冲 色散 自适应分步傅里叶方法

Numerical simulation on ultrashort laser pulses propagating in microstructure fi bers

For the first time to our knowledge, it is put forward that GNSE can be resolved by adaptive split-step Fourier method (ASSFM) basing on split-step Fourier method (SSFM) in this paper. It is found that ASSFM must be used to resolve GNSE f or ensuring precision when the frequency shift corresponding to soliton peak val ue is remarkable and microstructure fibers' parameters change along with frequen cy remarkably. It is found that the influence of dispersion on laser pulses evol ution and supercontinuum generation in microstructure fiber is remarkably. Mech anism and scope of expanded spectrum are different in fiber different dispersion regions. The precision of numerical simulation by ASSFM is higher than SSFM in the process of laser pulses propagating in microstructure fibers by reason that the variation of wavelength corresponding to pulse peak power can be considered adequately.