1ST OBSERVATION OF FORCES ON 3-LEVEL ATOMS IN RAMAN RESONANT STANDING-WAVE OPTICAL-FIELDS

A sodium atomic beam is deflected by two optical standing-wave fields which excite near resonance Raman transitions. Observed deflections are consistent with theoretical predictions of a long-range dc component of the force on a three-level atom in the LAMBDA-configuration. The low laser intensities (and small detunings) used, combined with observed evidence of damping in the three-level LAMBDA-system, may ultimately lead to the design of high-density, all optical traps wherein the atoms would be mostly in the dark state.