Nonsequential double ionization of atoms driven by few-cycle counter-rotating two-color circularly polarized laser fields

Abstract

Using a classical ensemble model, we investigated the dependence of nonsequential double ionization (NSDI) on the relative phase driven by few-cycle counter-rotating two-color circularly polarized (TCCP) laser fields, which consist of 1600-nm laser pulse and 800-nm laser pulse. The numerical results reveal that NSDI probability is strongly dependent on the relative phase of counter-rotating TCCP fields, which shows a sin-like behavior of period 2π. The inversion analysis shows that the returning probability of the first electron is very sensitive to the relative phase of counter-rotating TCCP fields, resulting in dependence of NSDI probability on the relative phase. Furthermore, the dynamic behavior of two electrons can be regulated by adjusting the relative phase, leading to the sensitive dependence of momentum distribution of Ar2+ ions on the relative phase of counter-rotating TCCP fields. In addition, our results show that the traveling electron can be controlled to return to the parent ion core from a relatively single direction, which leave an imprint on the momentum distribution of Ar2+ ions.