Title: Structure & Condensation of Exciton-Polaritons in Lead Halide Perovskite Optical Cavities
Description: Lead Halide Perovskites (LHPs) have emerged as an outstanding optical material, chiefly as attractive options for studies of light emission, due to their high quantum efficiencies, broad wavelength tuneability via chemical substitution, and facile growth conditions. LHPs have also been increasingly considered as an ideal candidate for exploring applications of exciton-polariton condensation, with a recent explosion of research in this area. The physical properties of LHPs are distinct from traditional materials often used to study exciton-polaritons, leading to debates over photo-physical mechanisms of stimulated emission, and interpretation of experimental results. This thesis addresses these debates in two parts, discussing (1) how the relatively low exciton-binding energy and phonon-bottleneck effects often leads to exciton dissociation prior to the laser powers needed to observe stimulated emission, and (2) how the optical birefringence associated with bulk CsPbBr3 at cryogenic temperatures will produce novel optical potentials which amount to a synthetic spin-orbit coupling of exciton-polaritons within a perovskite microcavity.

These conclusions are reached by a combination of static and time-resolved spectroscopies, along with polarization-resolved Fourier-imaging optical techniques.