Organic microcavities with anisotropic optically active materials

We study the eigenmodes and the linear optics of an organic bulk microcavity whose active layer is formed of oriented molecular aggregates. Such active medium can be considered microscopically as uniaxial with optical axis determined by the orientation of the dipole moment of the excitonic transition. Using the 4 x 4 transfer matrix formalism we calculate the cavity polariton dispersion and the reflection and transmission spectra as a function of the in-plane wavevector, with special attention to the birefringent effect and to the formation of mixed symmetry polariton branches.