Electron transition dynamics in high-order harmonic generation process from H2+

Abstract

The high-order harmonic generation from [Formula: see text] has been theoretically investigated by numerically solving the two-dimensional time-dependent Schrödinger equation. A sharp minimum can be seen in the harmonic spectrum for larger internuclear distance. Moreover, the electron transition process between the ground state and the first excited state competes with the ionization process at larger internuclear distance, which is the main reason of the spectral minimum. By superposing the static electric field and adjusting the orientation angle [Formula: see text], it is further proved that the electron transition frequency between two lowest electronic states can be decoded by the minimum.