Spatial distribution of molecular harmonic emission from H2+

Abstract

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

CLC Number:

O562.4

References

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