Enhanced Raman scattering in a strongly coupled microcavity containing J-aggregates

We report the first observations of resonant Raman scattering in the strong coupling regime for a planar microcavity containing J-aggregates of a cyanine dye. Cavities were constructed by depositing a 180 nm thick film of a transparent matrix polymer containing the cyanine dye J-aggregates between a high-reflectivity dielectric mirror and a silver mirror. We measure a Rabi splitting between the polariton branches of 88 meV. Using resonant optical-excitation of the lower polariton branch, we observed both Stokes and also anti-Stokes Raman scattering between different lower branch polariton states. In contrast to strongly coupled microcavities based on inorganic semiconductors, the high binding energy of organic excitons permits the observation of the anti-Stokes resonant Raman process in a microcavity for the first time. Compared to control J-aggregate films, we observed an enhancement in the Raman scattering efficiency of approximately 300 times. This enhancement occurs as a result of the significantly enhanced photon-confinement that occurs in high finesse microcavity structures. Our observations of polariton scattering in organic microcavities suggest that such structures will be of significant interest in the study of non-linear bosonic processes.