Electron drift directions in strong-field double ionization of atoms

Stanley L. Haan, Calvin University
Z. S. Smith, Calvin University
K. N. Shomsky, Calvin University
P. W. Plantinga, Calvin University

Abstract

Longitudinal momentum spectra and electron drift directions are considered for several laser wavelengths in non-sequential double ionization of helium using three-dimensional classical ensembles. In this model, the familiar doublet for wavelength 800 nm and intensities of order 5 × 1014 W cm-2 becomes a triplet for wavelength 1314 nm, then a doublet for 2017 nm. The results are explained based on whether the post-ionization impulse from the laser results in backward drift for one or both electrons. © 2009 IOP Publishing Ltd.