Polariton states of cavity coupled three-level atoms

We study a cavity quantum electrodynamics system in which a cavity mode couples simultaneously with two separate transitions of three-level atoms, and show that three polariton states are created in the coupled cavity-atom system. We report the observation of such polariton states in an experiment with cold Rb atoms confined in a cavity. The experimental results agree with theoretical calculations based on a semiclassical analysis. The three-level cavity-atom system may be used for a variety of fundamental studies and practical applications.