Nonsequential double ionization of xenon by linearly and elliptically polarized ultra-short laser pulses

With a fully classical ensemble model, we investigate the nonsequential double ionization (NSDI) of Xe by linearly polarized (LP) and elliptically polarized (EP) ultra-short laser pulses respectively. For these two cases, the momentum distributions of correlated electron in the direction of parallel to the laser field (for LP) and along the long axis of the laser polarization plane (for EP) show significant difference, but along perpendicular to the laser field (for LP) and the short axis of the laser polarization plane (for EP), the momentum distributions often emit into the opposite hemisphere. By back analyzing the classical trajectories of NSDI, it shows that the recollision is still the underlying mechanism. For LP, the recollision often occurs at the first returning of tunneled electron, but for EP, all of the successful NSDI come from the “exit collision” [PRA 81, 023409 (2010)] which is responsible for the momentum distribution of correlated electron. Moreover, for LP, we divide the trajectories of NSDI into four cases based on the time delay between singly ionization and recollision, and find the ionization mechanism is different for them, so the momentum distribution of correlated electron exhibits a strongly distinction.