Dual band Vis-IR absorber using bismuth based helical metamaterial surface

Abstract

In this study authors worked to attain a metamaterial absorber for visible and infrared region using bismuth as its main constituent material. Proposed absorber would be used for various applications; solar cell, communication etc. To model the metamaterial surface, two different sets of materials are used to observe and compare the absorption, having metal-insulator-metal structure to observe the metamaterial. It is observed that proposed metamaterial layer having Al/TiO\(_2\)/Bi, displays high absorption for two bands in different wavelength region with wide bandwidth. Absorption peaks are observed at 510 nm and 1590 nm. However, apart from the peaks, absorption is not less than 0.5 a.u. anywhere in the absorption spectrum, which depicts that this absorber can be used for whole wavelength range varies from 200 to 2500 nm. Designed absorber in this study also ensures the easy fabrication of the metamaterial surface due to its less complex design and small geometry, which ensures the stability of three dimensional structure.