Pathways modulation of atomic non-sequential double ionization via few-cycle counter-rotating two-color laser fields

We analyze ultrafast electron correlation effects in non-sequential double ionization (NSDI) of argon atoms induced by few-cycle counter-rotating two-color circularly polarized (TCCP) laser pulses, employing the three-dimensional classical ensemble model (CEM). Our results demonstrate that the amplitude ratio of externally driven laser pulses can modulate the dynamic behavior of two electrons, thereby controlling the travel time and trajectory of the first ionized electron in the electric field. This allows the first ionized electron to accumulate more energy in the electric field, which in turn influences the relative contributions of the recollision induced ionization (RII) mechanism and the recollision excitation with subsequent ionization (RESI) mechanism.