Dark-state-based three-element vector model for the stimulated Raman interaction

In this paper we develop a three-element vector model to describe the stimulated Raman interaction in a L system. This model is valid over the range of interaction energies for which the excited state follows the ground states adiabatically. We use the model to present simple physical interpretations of the generation of Raman-Ramsey fringes in a separated field excitation, the ac Stark shift in the Raman clock, the ultrahighresolution mapping of microwave phase using Raman probes, and the coherent transfer of population by adiabatic passage for atomic beam splitters. The expressions for observables are derived by inspection and agree quantitatively with published experimental results. @S1050-2947~97!00302-8#