Optical strong coupling in microcavities containing J-aggregates absorbing in near-infrared spectral range

We present strong exciton–photon coupling at near-infrared wavelengths in an organic microcavity containing J-aggregates of a cyanine dye. Strong coupling is resolved using position-tuned transmission measurements, performed at room temperature at a constant angle. Clear anti-crossing around the organic exciton energy (1.57 eV = 789 nm) is observed with a Rabi splitting energy of 68 meV. Such systems will be of significant interest in the creation of hybrid semiconductor structures in which organic and inorganic excitons are electromagnetically coupled. We have also investigated the photostability of the J-aggregates used in the experiments and compare it with other cyanine dyes forming J-aggregates from water-based solutions. Our measurements suggest that the near-infrared dye is exceptionally stable in vacuum, especially at low temperatures.