Vacuum-field Rabi splitting in the presence of inhomogeneous broadening: Resolution of a homogeneous linewidth in an inhomogeneously broadened system

We study the effect of inhomogeneous broadening of the electronic state on vacuum-field Rabi splitting. The broadening has no effect on the size of the splitting and, in general, does not lead to an inhomogeneous broadening of the split states. From a spectroscopic point of view, these results have interesting consequences, since they allow the extraction of a homogeneous line in an inhomogeneously broadened system. \textcopyright{} 1996 The American Physical Society.