Room temperature polariton luminescence from a GaN∕AlGaN quantum well microcavity

Abstract

The authors report on the demonstration of strong light-matter coupling at room temperature using a crack-free UV microcavity containing GaN∕AlGaN quantum wells (QWs). Lattice-matched AlInN∕AlGaN distributed Bragg reflectors (DBRs) with a maximum peak reflectivity of 99.5% and SiO2∕Si3N4 DBRs were used to form high finesse hybrid microcavities. State-of-the-art GaN∕Al0.2Ga0.8N QWs emitting at 3.62eV with a linewidth of 45meV at 300K were inserted in these structures. For a 3λ∕2 microcavity containing six QWs, the interaction between cavity photons and QW excitons is sufficiently large to reach the strong coupling regime. A polariton luminescence is observed with a vacuum field Rabi splitting of 30meV at 300K.