Strong coupling in high-finesse organic semiconductor microcavities

Abstract

We report the fabrication of high-finesse strongly coupled microcavities composed of a polystyrene film doped with the dye tetraphenyl–porphyrin zinc positioned between two high reflectivity dielectric mirrors. The bottom mirror was deposited by plasma enhanced chemical vapor deposition, and was composed of 11 λ/4 thick (silicon oxide/silicon nitride) pairs. The organic layer was deposited on to this by spin coating. Finally, the top mirror was deposited by thermal evaporation and consisted of 12 λ/4 thick (tellurium oxide/lithium fluoride) pairs. Such cavities are characterized by Q factors of between 440 and 620. Strong coupling was evidenced via white light reflectivity measurements. Due to the high cavity Q factor, a Rabi splitting of 135 meV at resonance was very clearly resolved.