Quantum optics in dispersive and absorptive media

Using microscopic models in which both photons and excitons are treated as microscopic degrees of freedom, we discuss polaritons of two cases: one is the case where excitonic parameters are time dependent. The time dependence causes the creation of polaritons from a ‘false vacuum.’ It is shown that both the creation spectra and the creation efficiency are very different from the results of previous studies. The other case is that of polaritons in absorptive and inhomogeneous cavities. A polariton in such a system cannot be viewed as a back-and-forth oscillation between a photon state and an exciton state.