Halide Perovskite Microplates Coupled with Optically Resonant Silicon Nanoparticles

Halide perovskite microplates have outstanding luminescent and electronic properties, being a versatile tool both for photonics and optoelectronics. Their most perspective applications are microlasers, light-emitting devices, photodelectors, and even polaritonic calculations. Their high-quality crystallinity is responsible for their perfect geometrical shape and very smooth surfaces of the facets. However, such a high-quality shape results in the trapping of luminescence generated from the bulk of the microplates owing to perfect internal reflection. This effect reduces the out-coupling efficiency from the upper facet and, thus, makes the light-emitting device performance less efficient. Here we apply silicon nanoparticles supporting Mie resonances for the efficient photoluminescence out-coupling from the CsPbBr 3 microplates. Our experimental and theoretical studies confirm that even 150 nm silicon nanoparticle with resonant response around a wavelength of 500–550 nm can out-couple the waveguiding modes in perovskite sufficiently. We believe that such nanophotonic approach for local subwavelength emission control will be suitable for many applications.