Broadband Antireflection with Halide Perovskite Metasurfaces

Meta‐optics based on optically resonant dielectric nanostructures is a rapidly developing research field with many potential applications. Halide perovskite metasurfaces have emerged recently as a novel platform for meta‐optics, and they offer unique opportunities for control of light in optoelectronic devices. Here, the generalized Kerker conditions are employed to overlap electric and magnetic Mie resonances in each meta‐atom of MAPbBr₃ perovskite metasurface, and broadband suppression of reflection down to 4% is demonstrated. Furthermore, it is revealed that metasurface nanostructuring is also beneficial for the enhancement of photoluminescence. These results may be useful for applications of nanostructured halide perovskites in photovoltaics and semi‐transparent multifunctional metadevices where reflection reduction is important for their high efficiency.