Hybridization of plasmonic and dielectric metasurfaces with asymmetric absorption enhancement

Surface plasmon resonance (SPR) is widely utilized to improve the capabilities of nanophotonic devices, such as nanoantennas, plasmonic photovoltaics, and photocatalysts. In order to further enhance the absorption efficiency, high refractive index (HRI) materials are used to enhance absorbability. The desired absorber properties can be realized by combining the SPR and Mie resonance of HRI nanostructures. In this study, the asymmetric absorption enhancements are demonstrated by combining the Mie resonance of silicon nanopillars and the localized SPR of gold nanodisks. In order to increase the possibility of this design in future applications, TiO2 and Ge also present the same phenomenon. For mass production, the nanostructure design of absorbers can be simplified and made suitable for the current semiconductor process technology.