光纤中的非线性效应对高斯光脉冲传输的影响

非线性效应和色散都是影响光脉冲在光纤中传输的重要因素,在反常色散区,色散和非线性效应的相互平衡可实现光孤子传输;在正常色散区,二者的相互作用可用于光脉冲的压缩.因此,两种效应对光脉冲传输的影响一直受到人们的广泛关注.从光脉冲的非线性薛定谔方程出发,在忽略色散的条件下,推导并模拟了自相位调制(SPM)非线性效应下的高斯光脉冲的非线性相移、频率啁啾;数值模拟了SPM下不同最大相移时无啁啾和有正啁啾时高斯光脉冲的频谱.讨论了SPM效应对高斯光脉冲频谱的影响.

Effects of nonlinear effects in optical fibers on propagation of Gauss optical pulses

Both the nonlinear effects and the chromatic dispersion are important factors affecting the optical pulse which propagates in the optical fiber. In the abnormal chromatic dispersion region the balance of the chromatic dispersion and the nonlinear effect can realize the optical soliton propagation. In the normal chromatic dispersion region the interaction between them can be used in the compression of the optical pulse. Therefore the two effects in the optical pulse propagation are paid widespread attention. Starting from the nonlinear Schroedinger equation of the optical pulse and neglecting the chromatic dispersion the nonlinear phase shifts and frequency chirps of the Gauss optical pulses caused by the self-phase modulation (SPM) are derived and computer simulated. The frequency spectra of the Gauss optical pulses with positive and without initial chirps are numerically simulated for different maximum phase shifts. The effects of SPM on the frequency spectra of the Gauss optical pulses are discussed.