H2+分子谐波发射的空间分布

摘要/Abstract

摘要： 理论研究了H2+分子发射高次谐波的空间分布情况。结果表明：分子谐波主要发生在两个H核附近。当核间距离较小时，两个H核发射谐波强度几乎一致。核间距离增大，正向H核发射谐波强度要大于负向H核。随着空间非均匀激光场的引入，H2+分子在较小核间距离时，负向H核发射谐波强度要略大于正向H核。在较大核间距离时，正向H核发射谐波强度要大于负向H核。但是随着空间非均匀激光场引入位置从负向移动到正向(-100 a.u.到100 a.u.)，正向H核发射谐波强度逐渐减小。最后，通过叠加谐波可获得脉宽在66 as和62 as的超短脉冲。

关键词: 阿秒脉冲

Abstract: Spatial distribution of the harmonic generation from H2+ has been theoretically investigated. The results show that the molecular harmonic emissions main occur around the two H nuclei. In smaller internuclear distance, the harmonic intensities from the two H nuclei are almost the same. As the internuclear distance increased, the harmonic intensity from the positive-H nucleus is higher than that from the negative-H nucleus. With the introduction of the spatial inhomogeneous laser field, the harmonic intensity from the negative-H nucleus is higher than that from the positive-H nucleus in smaller internuclear distance. While, in larger internuclear distance, the harmonic intensity from the positive-H nucleus is higher than that from the negative-H nucleus. However, as the spatial position of the inhomogeneous field moving from the -100 a.u. to the 100 a.u., the harmonic intensity from the positive-H nucleus is decreased. Finally, by properly selecting particular harmonics orders, the ultrashort attosecond pulses with durations of 66 as and 62 as can be produced.

Key words: attosecond pulse

中图分类号:

O562.4

刘航冯立强刘辉. H2+分子谐波发射的空间分布[J]. J4, 2018, 35(1): 54-62.

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