title: Slow electrons generated by intense high-frequency laser pulses.
abstract: A very slow electron is shown to emerge when an intense high-frequency laser pulse is applied to a hydrogen negative ion. This counterintuitive effect cannot be accounted for by multiphoton or tunneling ionization mechanisms. We explore the effect and show that in the high-frequency regime the atomic electron is promoted to the continuum via a nonadiabatic transition caused by slow deformation of the dressed potential that follows a variation of the envelope of the laser pulse. This is a general mechanism, and a slow electron peak should always appear in the photoelectron spectrum when an atom is irradiated by a high-frequency pulse of finite length.
authors.affiliation: Department of Applied Physics and Chemistry, University of Electro-Communications, 1-5-1, Chofu-ga-oka, Chofu-shi, Tokyo, Japan.
authors.forename: Koudai
authors.initials: K
authors.lastname: Toyota
authors.forename: Oleg I
authors.initials: OI
authors.lastname: Tolstikhin
authors.forename: Toru
authors.initials: T
authors.lastname: Morishita
authors.forename: Shinichi
authors.initials: S
authors.lastname: Watanabe