A broadband and polarization-independent metamaterial perfect absorber with monolayer Cr and Ti elliptical disks array

Abstract

We design a broadband perfect metamaterial absorber from visible to near infrared regime consisting of monolayer Cr and Ti elliptical disks array located on the SiO2-Au layer. The bandwidth for the absorption above 90% reaches about 1140 nm and above 99% reaches about 584 nm. The high absorption and broadband obtained mainly come from the mode of the plasma excitation. The broadband perfect absorber we demonstrate here, is insensitive to the incident polarizations, which shows great potential value in high-temperature photonic applications, such as solar energy harvesting, light trapping.