Strong exciton-photon coupling in an organic single crystal microcavity

We demonstrate strong exciton-photon coupling of Frenkel excitons at room temperature in a microcavity composed of a melt grown thin film anthracene single crystal and two distributed Bragg reflectors. Angle-resolved reflectivity and normal incidence photoluminescence under weak excitation are observed. The microcavity spectrum is a function of the anisotropy of the crystalline material and the strong exciton-photon coupling of the excitonic resonances to the cavity photon. The photoluminescence spectrum is found to be completely polarized along the crystal axes.