论文部分内容阅读
在正常色散条件下,超短光脉冲在光纤放大器中可以演化成具有线性啁啾的自相似抛物脉冲,其演化结果可影响脉冲的压缩质量.采用分步傅里叶方法数值研究了正常色散光纤放大器中,初始输入脉冲宽度、能量、光纤增益和色散系数对超短脉冲自相似演化结果的影响.发现色散长度是脉冲能否实现自相似演化的关键因素.当色散长度与光纤长度相近(几倍)时,脉冲可以实现自相似演化;两者相差越大,脉冲的自相似演化程度越差.增加初始脉冲能量可以加速脉冲的自相似演化,缩短自相似演化的距离.放大器总增益一定时,增益系数越大,脉冲受非线性扭曲的影响越大,使脉冲的自相似演化结果越差;增益系数为0.95 m-1时放大器可获得的总增益比3.8 m-1时大3.3 dB.
Under normal dispersion conditions, the ultrashort optical pulse can evolve into a self-similar parabolic pulse with linear chirp in the fiber amplifier, and its evolutionary effect can affect the compression quality of the pulse.The numerical simulation of normal dispersion fiber In the amplifier, the effect of the initial input pulse width, energy, fiber gain and dispersion coefficient on the self-similar evolution of the ultrashort pulse was investigated. It was found that the dispersion length is the key factor for whether the pulse can achieve self-similar evolution. The pulse can self-similar evolution, the greater the difference between the two is, the worse the self-similar evolution of the pulse.The increase of the initial pulse energy can accelerate the self-similar evolution of the pulse and shorten the distance of self-similar evolution.When the total gain of the amplifier is constant , The bigger the gain coefficient is, the bigger the pulse is affected by the non-linear distortion, the poorer the self-similar evolution of the pulse is. When the gain coefficient is 0.95 m-1, the total gain of the amplifier is 3.3 dB larger than that of 3.8 m-1.