Pathway competition of H+ in intense femtosecond laser fields

Abstract

We experimentally measured the kinetic energy and angular distributions of fragment ion H+ of H2 as a function of 810 nm femtosecond laser intensity by using velocity map imaging technique. The reasonable origination of dissociation channels (1.0) and (1.1) are proposed. The analysis of the angular distribution indicates the net two-photon pathway via the 3ω crossing dominates over the direct one-photon pathway in channel (1.0). The relative yield of fragment peaks indicates that dissociation and ionization of H2+ are competitive. The lower laser intensities emphasize the dissociation probability of H2+, and the higher laser intensities favor higher ionization stages.