Relativistic dynamics of electrons in intense laser fields

Following a brief review of the analytic solution for the relativistic motion of a single electron in a pulse of very strong plane-wave radiation, numerical simulations are presented that probe the effects of space-charge forces and spatial inhomogeneity of the radiation upon the one-electron dynamics. The nonlinearities introduced by relativistic effects can lead to irregular dynamics. For pulses with a smoothly varying temporal envelope the behavior of electrons that are ionized during the pulse can be very different from that of ambient electrons. The calculations support the use of short-pulsed lasers to produce high-energy electrons and incoherent x rays, but reveal possible difficulties in the formation of cold overionized plasmas suitable for recombination lasers.