Nuclear momentum distributions governed by Rabi flopping in the dissociation of hydrogen molecular ions in strong laser fields

Abstract

We study the Rabi flopping between the $1s{\ensuremath{\sigma}}_{g}$ and $2p{\ensuremath{\sigma}}_{u}$ states during the dissociation of hydrogen molecular ions in strong laser fields by numerically simulating the time-dependent Schr\"odinger equation. Starting either from a certain vibrational state or from coherently superimposed vibrational states weighted with Frank-Condon factors, the dissociative nuclear momentum distributions present multiple angular nodes and maxima due to molecular alignment-dependent Rabi flopping. The Rabi frequency and nuclear angular distribution depend on the laser chirp and laser ellipticity. Rabi flopping also determines the population on the $2p{\ensuremath{\sigma}}_{u}$ state and thus the dissociation probability. The deep understanding of Rabi flopping in molecular dissociation gives clues to control ultrafast molecular dynamics.