One of the "J. Phys. B's 2005 Highlights", selected by the editors of the Journal of Physics B "Strong laser field ionization of Kr: first-order relativistic effects defeat rescattering"

E Gubbini, U Eichmann, M Kalashnikov and W Sandner, Max-Born-Institut Berlin

The magnetic component of light waves can be neglected in most cases over the electrical. This does not apply to ultra-strong laser fields that can release electrons from atoms and accelerate them to relativistic velocities. In the present experiment, a magnetic deflection of the order of only a few atomic diameters was detected with high precision.
J. Phys. B: At. Mol. Opt. Phys. 38 No 6 (28 March 2005) L87-L93