Eur. Phys. J. D 62, 227-236 (2011)
https://doi.org/10.1140/epjd/e2011-10438-4

Influence of the sign of the refractive index in the reflectivity of a metamaterial surface with localized roughness

Grupo de Electromagnetismo Aplicado, Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria Pabellón I, C1428 EHA Buenos Aires, Argentina

^a e-mail: rdep@df.uba.ar

Received: 4 August 2010
Received in final form: 10 December 2010
Published online: 11 March 2011

Abstract

To study the scattering properties of metamaterials, we generalize two scattering methods developed for conventional (non-magnetic) isotropic materials to the case of materials with arbitrary values (positive or negative) of magnetic permeability and electric permittivity. The generalized methods are used to study the changes produced in the reflectivity of a metamaterial surface with localized roughness when the relative refractive index changes sign. Our results show that, unlike the case of a plane surface whose reflectivity is unaffected by the change of sign of the relative refractive index, in rough surfaces the change of sign is manifested in the reflectivity, even for very low roughness, particularly in observation directions away from the specular direction.