Room Temperature Broadband Polariton Lasing from a CsPbBr3 Perovskite Plate

Tunable polariton lasing is demonstrated from an all-inorganic CsPbBr₃ perovskite microcrystal plate over 23 nm in the green part of the optical spectrum, operating at room temperature. The emission spectrum is controlled by adjusting the effective length of a multi-$\lambda$ planar microcavity, whilst observing the hallmarks of polariton condensation under non-resonant excitation. Furthermore, simultaneous condensation is observed into two non-degenerate lower polariton branches of orthogonal polarizations induced by anisotropy of the perovskite crystal.