Spatial distribution on high-order-harmonic generation of anH2+molecule in intense laser fields

Abstract

High-order-harmonic generation (HHG) for the ${{\mathrm{H}}_{2}}^{+}$ molecule in a 3-fs, 800-nm few-cycle Gaussian laser pulse combined with a static field is investigated by solving the one-dimensional electronic and one-dimensional nuclear time-dependent Schr\odinger equation within the non-Born-Oppenheimer approximation. The spatial distribution in HHG is demonstrated and the results present the recombination process of the electron with the two nuclei, respectively. The spatial distribution of the HHG spectra shows that there is little possibility of the recombination of the electron with the nuclei around the origin $z=0$ a.u. and equilibrium internuclear positions $z=\ifmmode\pm\else\textpm\fi{}1.3$ a.u. This characteristic is irrelevant to laser parameters and is only attributed to the molecular structure. Furthermore, we investigate the time-dependent electron-nuclear wave packet and ionization probability to further explain the underlying physical mechanism.