Electric field enhancement of the Rabi splitting in a superlattice-microcavity system

We have observed a large coupling between the photonic mode of a microcavity and Stark-localized excitons from a superlattice embedded in it. The coupling is significantly stronger than in comparable microcavities that contain quantum wells solely at the antinodes. The large density of exciton states in a superlattice and their large binding energy, once they are confined by an electric field, explain this enhancement.