NEW COMPUTATIONAL METHOD FOR ATOMS IN AN INTENSE ELECTROMAGNETIC-FIELD

A new representation is found for the interaction of intense circularl y polarized light with an atom. A stationary centrosymmetric part, whi ch depends on the field parameter a(0)=F/omega(2), is separated out fr om the atom-field interaction. The time-dependent part of die interact ion is represented in the form of a multipole expansion with ao taken into account. The application of this representation for calculating t he nonlinear dynamic polarizability of a complicated atom in the rando m-phase approximation with exchange is studied. (C) 1998 American Inst itute of Physics.