Electromagnetic Characterization of Graphene-Plasma Formations

This article presents an efficient electromagnetic (EM) characterization technique to extract the permeability and permittivity tensors of multilayer graphene-plasma formations. This method uses the scattering parameters of normally incident circularly polarized plane waves in free space, making use of the circular polarization to deal with the discontinuity ambiguities in the extracted tensorial permeabilities and permittivities. The proposed method directly determines the linear permeability and permittivity tensors from the combined parameters that are deduced from the circularly polarized wave components. This simple procedure succeeds in overcoming the limitation to usable terahertz and optical frequency bands suffered by existing extraction techniques for lossy and lossless anisotropic material behavior. The retrieved graphene-plasma tensor elements are validated by means of comparison with analytical parameters obtained by solving the original EM problem using the transfer matrix method extended for the circularly polarized fields.