【摘要】 针对线性啁啾的宽频带激光,分析了采用角谱色散(ASD)方法实现Ⅰ/Ⅱ类角度失谐的KDP晶体三倍频方案,讨论了光栅角色散、入射基频光的光强、带宽以及晶体厚度对三倍频转换效率、脉冲波形和光谱分布的影响,并对采用角谱色散补偿法的宽带三倍频方案参数进行了优化。研究结果表明,采用ASD方法,不仅能有效地提高带宽较宽条件下三倍频光的转换效率,而且还可以使三倍频光脉宽和带宽明显变宽、脉冲波形和光谱分布变光滑。经方案优化后,当入射基频光带宽11.2nm、光强2-6GW/cm2时的三倍频光转换效率可达到60%左右,比不采用ASD时的三倍频光转换效率提高了40%左右。更多还原

【Abstract】 As for the linear chirped broadband laser,the type l/Il angle-detuning KDP crystal scheme for third harmonic generation by using angular spectral dispersion(ASD) method has been analyzed.The effects of the grating dispersion parameter,the intensity and bandwidth of the incident fundamental field,as well as the length of the KDP crystal on the third harmonic conversion efficiency,the pulse shape and spectral distribution of the third harmonic field have been discussed.The parameters for the broadband third harmonic conversion scheme have been optimized.The results show that the conversion efficiency,the pulse width and the bandwidth of the third harmonic field increase significantly and the pulse shape and spectral distribution become smooth by using grating angular spectral dispersion.For the incident fundamental field with the bandwidth of 11.2 nm and the intensity of 2～6 GW/cm~2,the third harmonic conversion efficiency of about 60 % can be achieved,which has increased about 40 % compared with the case without ASD method.更多还原