三阶群速度色散导致超短脉冲畸变的研究

RESEARCH OF ULTRASHORT OPTICAL PULSE DISTORTION BY THIRD ORDER GROUP VELOCITY DISPERSION

本文基于超短光脉冲在单模光纤中传输时满足的高阶修正的非线性薛定谔方程理论,在仅考虑光纤三阶色散效应时,推导出无啁啾的高斯脉冲沿单模光纤传输时脉冲变化的表达式,并对理论结果进行了数值模拟,分析了脉冲产生畸变的影响因素.结果表明,三阶色散效应会引起超短光脉冲的一个沿形成非对称的拖尾振荡结构,脉冲形状发生严重畸变,降低输出的信噪比(SNR),导致光信号传输质量的下降.

On the theoretic basis that ultrashort optical pulse meets the high order nonlinear Schrdinger (HONLS)equation propagating along single-mode fiber, the analytic expression is derived by taking into account the third-order dispersion as an Gauss pulse without chirp propagates along the single-mode fiber, and the results are numerically simulated. The authors analyzed the influential reason of distortion of pulse.The results show that the third-order dispersion generates a unsymmetrical oscillatory trail structure at one of ultrashort pulse edges and the shape of pulse generates serious distortion ,reducing the output signal-to-noise ratio(SNR) and transmission quality of optical signal.