核运动对H2+和D2+谐波截止区域强度的影响

Effect of nuclear motion on harmonic cutoff intensity of H2+ and D2+

摘要:

理论研究了不同激光条件下H2+和D2+谐波截止附近区域强度的变化. 结果显示，在低激光强度下，当采用短脉宽激光场时，H2+谐波强度大于D2+谐波强度. 随着脉宽增大，D2+谐波强度增强并且大于H2+谐波强度. 在高激光强度下，当采用短脉宽激光场时，虽然H2+谐波强度依然大于D2+谐波强度，但其强度差比低激光强度时有所减小. 当采用长脉宽激光场时，D2+谐波强度大于H2+谐波强度. 理论分析表明，不同尺度的核运动是导致H2+和D2+谐波辐射强度不同的原因.

Abstract:

The intensity of harmonic cutoff region of H2+ and D2+ driven by different laser conditions has been studied theoretically. The results show that for the lower laser intensity case, the harmonic yield of H2+ is higher than that of D2+ when the shorter pulse duration is used. As the pulse duration increases, the harmonic yield of D2+ will be enhanced and higher than that of H2+. For the higher laser intensity case, when the shorter pulse duration is used, the intensity difference of harmonic yield is decreased, though the harmonic yield of H2+ is still higher than that of D2+. When the longer pulse duration is used, the harmonic yield of D2+ is much higher than that of H2+. Theoretical analyses show that the different harmonic yields of H2+ and D2+ is attributed to different time scales of nuclear motion.