Room temperature polariton emission from strongly coupled organic semiconductor microcavities

We report a room temperature study of the strong exciton-photon coupling re gime in a planar microcavity, containing cyanine dye aggregates with deloca lized exciton wave functions (J aggregates). Giant Rabi splittings of 80 me V between upper and lower polariton branches are observed and cavity polari ton emission is detected from the lower polariton branch. The small linewid th and large oscillator strength characteristic of J aggregates make them a favorable physical structure to allow the observation of strong coupling f or organic semiconductors. [S0031-9007(99)08927-9].