Steady state of atoms in a resonant field with elliptical polarization

Abstract

We present a complete set of analytical and invariant expressions for the steady-state density matrix of atoms in a resonant radiation field with arbitrary intensity and polarization. The field drives the closed dipole transition with arbitrary values of the angular momenta $J_g$ and $J_e$ of the ground and excited state. The steady-state density matrix is expressed in terms of spherical harmonics of a complex direction given by the field polarization vector. The generalization to the case of broad-band radiation is given. We indicate various applications of these results.

revtex, 26 pages, including 3 eps figures; PRA accepted for publication;v2 three typos are fixed