Ionization of atoms and molecules by a few-cycle laser pulse and interference effects in the rescattering process

We investigate the diffraction pictures arising due to strong-field ionization of a molecule in an ultrashort laser pulse and further field-induced recollision of the ionized electron with the parent molecular ion by direct numerical solution of the non-stationary Schrodinger equation. In molecules the angular distributions of the re-scattered electron are shown to differ dramatically from the simple usually used double-slit diffraction picture. The reason for this consists in the interference between scattered and non-scattered parts of the electron wave packet in the continuum. The found interference effect is demonstrated to play an important role in the formation of angular and momentum distribution both for molecules and atoms.