超短激光脉冲二倍频理论分析  

Theoretic analysis of second-harmonic generation of ultrashort laser pulse

作　　者：韩耀锋[1] 杨爱粉[1] 宁自立[1] 杜高社[1] 

机构地区：[1]西安应用光学研究所,陕西西安710065

出　　处：《应用光学》2007年第4期468-471,487,共5页Journal of Applied Optics

摘　　要：采用快速傅里叶变换(FFT)算法和Rung-Kutta法对KDP晶体中超短激光脉冲二倍频过程作了研究。详细讨论了群速度失配、群速度色散和三阶非线性相位调制效应对倍频光脉冲波形、光谱及转换效率的影响。研究结果表明:在超短激光脉冲二倍频中,三阶非线性相位调制效应可使二倍频光脉冲形状发生畸变,光谱明显展宽且转换效率降低;当入射基频光功率密度大于100GW/cm2时,三阶非线性效应是影响倍频过程的主要因素。FFT algorithm and Rung Kutta method were adopted to investigate the frequency doubling process of the ultrashort laser pulse in KDP crystal. The effects of group-velocity mismatch and dispersion, third-order nonlinear phase modulation on pulse shape, spectrum distribution and conversion efficiency of second-harmonic pulse were discussed. The results indicate that the modulation effect of the third-order nonlinear phase may distort the pulse shape of the frequency doubling, broaden the second-harmonic spectrum obviously and reduce the conversion efficiency. The third-order nonlinear phase modulation becomes the dominant factor to influence the process of the frequency doubling when the fundamental intensity of incident luminous power is over 100 GW/cm^2.

关 键 词：二倍频 三阶非线性效应 群速度失配 超短激光脉冲 

分 类 号：TN241-34[电子电信—物理电子学]