线性啁啾高斯脉冲堆积中的强度起伏频率

摘要

Intensity fluctuation in linearly chirped Gaussian pulse stacking(LCGPS) is studied systematically based on spectral analysis. Two-pulse LCGPS and multi-pulse LCGPS are analyzed with simulations based on Fourier transform. The variation of fluctuation frequencies with the number, chirp factor, time delay and pulse width of the Gaussian pulses is discussed in the case of multi-pulse LCGPS with inital pulses of the same amplitude and the same time delay. Finally a brief discussion is presented on the general case of multi-pulse LCGPS with initial pulses of different amplitude attenuation and different time delay. The results show that there are several separated frequency sidebands in the intensity spectrum of the stacked pulse, responsible for the intensity fluctuation. The higher frequency sidebands would have less contribution to the fluctuation due to smaller amplitude overlapping. The fluctuation frequencies increase with the growth of the chirp factor and time delay, and the decrease of pulse width of the initial Gaussian pulses.%基于谱分析方法系统研究了多个线性啁啾高斯脉冲堆积的强度起伏频率.首先基于傅里叶变换方法分别分析并模拟了两路和多路线性啁啾高斯脉冲堆积,讨论了等幅度、等延迟多路线性啁啾高斯脉冲堆积的情况下,起伏频率与初始高斯脉冲的数目与啁啾系数、时间延迟和脉冲宽度的关系,并简要分析了多路线性啁啾高斯脉冲堆积的一般情况.结果表明,在堆积脉冲的强度谱中存在一系列分立的频率边带,这些频率边带对强度起伏有贡献.高频的频率边带由于幅度交叠的部分较少,所以对强度起伏贡献较少.强度起伏频率随初始啁啾高斯脉冲啁啾系数和时间延迟的增大而增大,随脉冲宽度的减小而增大.