Fig. 3.

Density-dependent characterization of the hybrid exciton-polaritons. a–d False color intensity profile of the hybrid polariton device at different excitation powers, below (a), close to (b), at (c), and above (d) the threshold. The red dotted lines resemble the energy of the mode and serve to illustrate the blueshift at increasing excitation powers. e PL emission intensity (black) and linewidth (red) as a function of the excitation power. f Blueshift of the hybrid polariton mode across the condensation threshold. Inset: Blueshift above the threshold as a function of the polariton occupancy, which was normalized to unity at the threshold