Elastic scattering of polaritons in high quality microcavities and weak localization

We theoretically study the elastic scattering of lower cavity polaritons on the static disorder in high quality semiconductor microcavities in the strong coupling regime. We consider the dominant contribution of the resonant scattering on localized exciton levels and calculate for a model density of states the corresponding elastic mean free path and inhomogeneous broadening. Our analytical results compare well with available linewidth data and large scale numerical simulations. They also provide a justification for a widely used phenomenological model assuming the polariton wavevector conservation. Finally, we discuss the possibility of weak localization in state of the art microcavities.