Ultra-energetic electron ejection in relativistic atom - laser field interaction

The ionization process of an atom in an ultra-intense laser field is considered in a 2D and 3D classical relativistic approach with special attention being paid to the influence of the laser magnetic field and the breakdown of the dipole approximation. We show the possibility of generation of hot quasi-free electrons in the multi-MeV energy regime for feasible pulsed laser fields of intensity and wavelength . The redshift of the electron oscillation frequency with respect to that of the laser field, due to radiation-pressure-induced motion of the electron in the direction of laser pulse propagation, is used to explain previously unexpected energy boosts.