High Quality Factor in Solution-Processed Inorganic Microcavities Embedding CsPbBr₃ Perovskite Nanocrystals

Optical microcavities grant manipulation over light-matter interactions and light propagation, enabling the fabrication of foundational optical and optoelectronic components. However, the materials used for high-performing systems, mostly bulk inorganics, are typically costly, and their processing is hardly scalable. In this work, we present an alternative way to fabricate planar optical resonators via solely solution processing while approaching the performances of conventional systems. Here, we couple fully solution-processed high dielectric contrast inorganic Bragg mirrors obtained by sol-gel deposition with the remarkable photoluminescence properties of CsPbBr₃ perovskite nanocrystals. The approach yields microcavities with a quality factor of ∼220, which is a record value for solution-processed inorganic structures, and a strong emission redistribution resulting in a 3-fold directional intensity enhancement.