Broadband and omnidirectional absorption in heterostructures with a highly absorptive metallic film and a dielectric Bragg reflector

摘要

We have found theoretically that nearly total absorption in a wideband of frequencies and a large range of angles of incidence for both polarizations can be realized in a heterostructure consisting of a highly absorptive metal film and a truncated photonic crystal. Furthermore, the width of the absorption band is broadened with increase of the incident angle for the transverse electric polarization. Such properties are significant for designing near-perfect broadband and wide-angle absorbers in the visible and near infrared regions.