Un metamateriale per la realizzazione di assorbitori a RF

An artificial dielectric consisting of a bi-dimensional lattice of electric and magnetic minimum scattering antennas is proposed. The material is geometrically arranged as a lattice of Yee-like rectangularcells, each one consisting of a matched magnetic loop surrounded by four matched electric dipolesoccupying the rectangle corners. Such a planar array can be designed to constitute a virtually perfect absorber for a monochromatic wave impinging at normal incidence. The artificial dielectric, that we call double-dipolar medium, is studied by means of a mixed microscopic/macroscopic approach allowing to compute the equivalent permittivityand permeability of the metamaterial automatically taking into account dipole-dipole interactions. It is demonstrated for a dilute double-dipolar medium that both permittivity and permeability have a unitary real part and imaginary parts such to allow a full absorption of the impinging EM power. The efficiency of the absorber is investigated in terms of the lattice geometry