Polarization-insensitive and wide-angle absorber operating in the visible and near-infrared regimes

This paper investigates a wideband metamaterial absorber (MMA) operating in visible and near infrared regimes of electromagnetic spectra. The top metasurface of the proposed absorber is made of periodic cube-shaped rods made up of nickel metal and silicon dioxide. The wideband absorption of greater than 80% is achieved when operating from 400 to 1000 nm for normal incidence of light. The results show that the absorption of the absorber is due to the electric resonance of the MMA. Moreover, it was noticed that the polarization-insensitive nature of the MMA is due to the four-folded symmetry of the top Ni-SiO2 cube rods. The absorption was analyzed for the obliquity of the incidence of light. Besides that, the absorber shows large angular stability to the incidence light. The proposed absorber would be practical for solar heating and solar power generation, which can be used in light-based absorption applications.