Influence of the ground state wave function on the atomic high-order harmonic generation spectrum

doi:10.3969/j.issn.1000-5641.202022002

Abstract

Abstract:

High-order harmonic generation (HHG) may occur during the interaction between an intense laser field and an atom or molecule; HHG has become an important xtreme utility vehicle(XUV) light source which can be used to probe atomic and molecular structures. In this paper, we investigate the effect of the radial distribution of electric density on the HHG spectra by calculating the HHG spectrum of noble atomic gases in a polarized laser field using s and p orbital functions as ground state wave functions. The results show that the form of the wave function does not influence the cutoff value of the harmonic spectrum, which is determined by the ionization threshold energy and the laser intensity. However, different types of orbital wave functions do lead to different envelopes for the HHG spectrum. In particular, there is an additional dip in the plateau area for the p orbital case compared with the spectrum for the s orbital case. By analyzing the formula for the HHG spectrum, we attributed the dip position on the HHG spectrum to the density distribution of the ground state wave function in momentum space. This work may shed light on applications for using the HHG spectrum to visualize atomic orbitals.

Key words: envelope of high-order harmonic generation spectrum, s orbital, p orbital

CLC Number:

O437.1

Zhongyuan LI, Yingchun GUO, bingbing WANG. Influence of the ground state wave function on the atomic high-order harmonic generation spectrum[J]. Journal of East China Normal University(Natural Science), 2021, 2021(1): 103-111.

Figures/Tables 3

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