Dual broadband infrared absorptance enhanced by magnetic polaritons using graphene-covered compound metal gratings

Nghia Nguyen-Huu, Jaromir Pistora, Michael Cada
2019 Optics Express  
A dual broadband perfect absorber based on a graphene-covered compound silver (Ag) grating structure working in the infrared (0.8-2.1 µm) regime is proposed and investigated numerically. Two distinct absorption peaks approximately 1.0 are achieved by the excitation of magnetic polaritons over a large range of incident angles from 0 to 70 degrees. The physics underlying the structure is also explained by computing interactions of electromagnetic fields with the graphene and the Ag grating. In
more » ... e Ag grating. In addition, it has shown that the absorption peaks can be tuned by changing geometric parameters of the structure; however, their spectral shape and absorption remain unchanged. Furthermore, the proposed compound grating with a graphene overlay provides potential applications for infrared absorbing devices.
doi:10.1364/oe.27.030182 fatcat:4hjq3zvgmrhsxe5magyda64tfi