Very strong coupling in GaAs-based optical microcavities

We show that when following a simple cavity design metric, a quantum well exciton-microcavity photon coupling constant can be made substantially larger than the exciton binding energy in GaAs-based optical microcavities. Consequently the very strong coupling regime becomes accessible in which a strong asymmetry between upper and lower polariton branches may be observed experimentally. We further show that the corresponding polariton dissociation and saturation boundaries on the phase diagram are much extended, which suggests the possibility of constructing a room temperature, high power exciton-polariton laser without resorting to wide band-gap semiconductors.