Abstract

We theoretically investigate the sub-cycle electron dynamics in orthogonally polarized two-color laser fields by exact solution to the 3D time-dependent Schrӧdinger equation. The dynamics is also simulated by two semi-classical methods, namely, the quantum trajectory Monte Carlo simulation and the Coulomb-corrected strong field approximation. Through these methods, we identify the underlying mechanisms of the sub-cycle electron dynamics and find that both the nonadiabatic effects and the Coulomb potential play very important roles. The contribution of the nonadiabatic effects manifest in two aspects, i.e., the ionization rate and the nonzero initial velocity at the tunneling exit. The Coulomb potential has a different impact on the electrons’ trajectories for different relative phases between the two pulses. In addition, we find that by varying the relative phase, one can significantly control the yields of the electrons ejected into the Rydberg states, which provides an effective way to generate a large portion of neutral atoms for their potential applications.

© 2015 Optical Society of America