通过数值求解广义非线性薛定谔方程,本文对光子晶体光纤中超连续谱的孤子俘获现象进行研究.利用交叉相关频率分辨光学开关(x-FROG)技术,观测并记录了超连续谱沿着光纤长度的演化,得到孤子俘获的整个过程.研究发现:当满足相位匹配条件时,孤子与非孤子辐射波发生四波混频,产生的俘获波频谱随着孤子红移而逐渐蓝移;增加抽运功率,孤子与俘获波的作用增强.为可调谐超短脉冲和超连续谱研究提供理论依据.
In this paper, we numerically study the soliton trapping of supercontinuum in photonic crystal fiber by solving generalized nolinear Schr6dinger equation. Using the cross-correlation frequency resolved optical gating (X-FROG) technique, the propagation of the supercontinuum is recorded along the fiber and the evolution of soliton trapping is observed. When the phase-matching condition is met, new frequency of the pulse trapping is generated from four-wave mixing of soliton with nonsolitonic radiation, and is continuously blueshifted while the soliton is redshifted. Higher pump-power shows the strong interaction between soliton and nonsolitonic radiation. Provided in the paper is a theoretical basis for tunable ultra-short laser pulses and supercontinuum researches.