title: Sub-laser-cycle electron pulses for probing molecular dynamics.
abstract: Experience shows that the ability to make measurements in any new time regime opens new areas of science. Currently, experimental probes for the attosecond time regime (10(-18) 10(-15) s) are being established. The leading approach is the generation of attosecond optical pulses by ionizing atoms with intense laser pulses. This nonlinear process leads to the production of high harmonics during collisions between electrons and the ionized atoms. The underlying mechanism implies control of energetic electrons with attosecond precision. We propose that the electrons themselves can be exploited for ultrafast measurements. We use a 'molecular clock', based on a vibrational wave packet in H(2)(+) to show that distinct bunches of electrons appear during electron ion collisions with high current densities, and durations of about 1 femtosecond (10(-15) s). Furthermore, we use the molecular clock to study the dynamics of non-sequential double ionization.
authors.affiliation: National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A OR6, Canada.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Niikura
authors.forename: F
authors.initials: F
authors.lastname: Légaré
authors.forename: R
authors.initials: R
authors.lastname: Hasbani
authors.forename: A D
authors.initials: AD
authors.lastname: Bandrauk
authors.forename: Misha Yu
authors.initials: MY
authors.lastname: Ivanov
authors.forename: D M
authors.initials: DM
authors.lastname: Villeneuve
authors.forename: P B
authors.initials: PB
authors.lastname: Corkum