In order to take full advantage of amplifier gain-bandwidth, and obtain a shorter pulse with higher power in the terminal, it is necessary to conduct a spectrum shaping before the seed pulse being injected into the main amplifier chain to compensate the effect of gain narrowing. A new method, based on the spatial grating with variable line-space for spectrum shaping of chirped laser pulse with the central wavelength at 1053 nm and line width 6 nm, is presented. The rigorous coupled-wave theory is used to analyze the characteristics of grating diffraction, and the results indicate that this method produces no phase distortion. The diffraction efficiency, as a function of the depth and period of groove, incidenct angle, and incident wavelength, is calculated and analyzed, respectively. With proper grating parameters, the spectrum modulation depth from 0.5% to 84% can be achieved.

为了充分利用放大介质的增益带宽, 获得脉宽更短, 功率更高的输出脉冲, 需要将输入到主放大链的种子脉冲进行光谱整形来补偿放大过程中的增益窄化效应。提出了利用变栅距反射光栅实现中心波长1053 nm, 谱宽6 nm啁啾脉冲的光谱整形。运用严格的光栅衍射耦合波理论分析光栅的衍射特性, 发现该方案不会引入相位畸变。分别计算和分析了刻槽深度、入射角大小、光栅周期以及入射光波长的变化对衍射效率的影响, 通过选取适当的光栅参量可获得0.5%～84%的光谱调制深度。

通过光线追迹法给设计的反射式单光栅展宽器建立了一个数学计算模型。利用这个数学模型计算和分析了元件失调对反射式单光栅展宽器二阶色散量和输出光束发散角的影响,并考虑了反射式单光栅展宽器中衍射光栅和球形凹面镜的尺寸与展宽器带通的关系。发现当平面反射镜M1的纵向偏离角为0.2°时,展宽器的二阶色散量最大,偏离角大于或小于0.2°时,展宽器的二阶色散量随之减小;得到了元件失调会增加输出光束发散角的结论;并发现展宽器中衍射光栅和球形凹面镜尺寸的有限大小对带通有限制作用。提出了利用反射镜M1纵向的适当偏离增大展宽器二阶色散量的方法,以及增大衍射光栅和反射镜尺寸来提高展宽器带通的方法,从而进一步减少展宽过程中的光谱剪切。

Nd∶doped-glass-based sub-picosecond laser system with the maximum peak power of greater than 20 tara watts and the energy on target surface of 16 J is accomplished by using the chirped laser pulse amplification technology. While the laser pulse is focused by an off-axis parabolic mirror, the power density on target surface of approximately 2×10 18 W/cm 2 is acquired. In the performed neutron experiment, a C 8D 8 plate target is placed on the focal spot of the off-axis parabolic mirror. The maximum neutron yield for a single shot reaches 2.4×10 4. Still some other related problems are discussed

利用啁啾脉冲放大技术，建成了一台基于钕玻璃放大器1053 nm波长的亚皮秒超短脉冲激光系统(SPS)。系统的输出峰值功率大于20 TW，靶面最高能量可达16 J，采用离轴抛物面反射镜聚焦，在靶面上获得2×10 18 W/cm 2的激光功率密度，以此激光脉冲轰击氘化聚苯乙烯平面靶，获得单次发射最高2.4×10 4个中子产额。对中子产生的机理进行了相关的讨论。

探讨了高功率激光对玻璃表面的破坏。测量了在200ｐｓ激光正入射照射下Ｋ8玻璃的破坏阈值。解释了样品输入面和输出面破坏阈值不同的原因。