Composite structure for two-state atoms in an optical cavity

Abstract

Experimental and theoretical investigations of the radiative processes of a collection of two-state atoms contained in a high-finesse optical cavity are reported. To make contact with previous work on this subject, we consider the usual regimens in which either the cavity or the atomic damping is dominant. However, of greater interest and relevance to our experiments is the regime of strong coupling that generates splittings and new features in the normal-mode structure of the composite atom-field system. We identify possible mechanisms for producing line shapes with subnatural linewidths. Our experimental investigations are conducted with two-state sodium atoms that interact with a single mode of an ultra-high-finesse optical cavity. The incoherent spectral density of the transmitted field is detected by optical heterodyne. We obtain good qualitative agreement between theory and experiment for the general features of the composite atom-field system as manifested in the spectral density of the transmitted field. Experiments to probe the response of the system to weak modulation of the incident field are in progress.