Ultra-broadband and wide-angle plasmonic light absorber based on all-dielectric gallium arsenide (GaAs) metasurface in visible and near-infrared region

High-performance and cost-effective broadband light absorbers are crucial for various optical applications, including solar energy harvesting, thermophotovoltaic systems, and integrated photoelectric devices. In this study, an ultra-broadband and wide-angle plasmonic light absorber (PLA) based on an all-dielectric gallium arsenide (GaAs) metasurface in the visible and near-infrared regions is proposed and numerically investigated. The unit-cell of the proposed PLA is consisted of all-dielectric GaAs cylinder resonator (CR) adhered on an ultra-thin GaAs spacer layer backed with a tungsten (W) substrate. Numerical simulation results show that the absorption peak of the proposed PLA is up to 99.85 %, 99.9 % and…