Quantum motion of laser-driven atoms in a cavity field

We investigate the quantum motion of coherently driven ultracold atoms in the field of a damped high-Q optical cavity mode. The laser field is chosen far detuned from the atomic transition but close to a cavity resonance. so that spontaneous emission is strongly suppressed but a coherent field builds up in the resonator by stimulated scattering. On one hand the shape of the atomic wave function determines the field dynamics via the magnitude of the scattering and the effective refractive index the atoms create for the mode. The mode intensity on the other hand determines, the optical dipole force on the atoms. The system shows rich coupled atom-field dynamics including self-organkation. self trapping, cooling or heating. In the limit of deep trapping we are able to derive a system of closed. coupled equations. for a finite set of atomic expectations values and the field. This allows to determine the self consistent ground state of the system as well as the eigenfrequencies and damping rates for excitations. (C) 2004 Elsevier B.V. All rights reserved.