Design and analysis of an ultra-thin dual-band metamaterial absorber for THz applications

In this paper, we consider the design and analysis of an ultra-thin dual-band metamaterial absorber in the THz regime with a thickness of about lambda_0/16 where lambda_0 is the free-space wavelength, at the higher operating frequency. We have observed both a narrowing of the frequency response and a broadening of the angular response obtained through the insertion of a conducting ground plane. To retrieve the effective electromagnetic parameters of the structure, we have applied a homogenization technique to extract the relative electric permittivity, magnetic permeability and wave impedance.