Optical properties of spatially dispersive Mie-resonant halide perovskite nanoparticles

We have proposed a mechanism explaining the unusual blue shift of photoluminescence peak in relatively large perovskite nanoparticles, where the quantum confinement effect is insignificant. We performed theoretical analysis of the absorption and scattering cross-sections of incident light in such nanoparticles in classical (local) and nonlocal cases. The blue shift for the scattering and absorption features in spectra around the exciton peak was obtained from the model, which can be related to that the previously observed shift of the luminescence peak in perovskite nanoparticles with a diameter less than 100 nm owing to the exciton nonlocality.