超高斯啁啾光脉冲在单模光纤中传输的演化行为

Transmission characteristics of Chirped super-Gaussian optical pulse in the single-mode optical fiber

本文从激光脉冲在单模光纤中传输所满足的非线性薛定谔方程出发,通过分步傅里叶变换方法,数值研究了超高斯啁啾光脉冲在单模光纤中脉冲形状的演化。研究表明,超高斯脉冲在单模光纤中传输将经历一个从近平顶、多峰、最后到单峰的演变过程,且高阶色散将引起脉冲形状发生畸变;在GVD和SPM效应的共同作用下,无啁啾的超高斯脉冲在特定条件下将出现孤子演变,具有正啁啾的超高斯脉冲在传输的初始阶段,脉冲形状的变化非常剧烈,而由于负初始啁啾减弱了非线性与色散效应引起的频率啁啾,所以其脉冲波形的变化平缓一些。研究表明,SPM产生的啁啾对入射脉冲的初始啁啾有一定的补偿作用。

Based on the nonlinear Schrodinger equation, the evolution of chirped super - Ganssian optical pulse propagating in the single - mode fiber has been investigated numerically by split - step Fourier method. The results show that super- Gaussian pulse＇s shape undergoes a variation from near- rectangular, multi - peak, and finally to single - peak, and the shape of pulse deform when high - order dispersion is considered. On the effects of GVD and SPM, super - Gaussian pulse which has no chirp becomes seliton at given conditions, and the shape of which has positive chirp deforms extremely at beginning of propagation, but gently for which has negative chirp. Furthermore, chirp caused by SPM conapensates the initial chirp of input pulse in some degree.