Extraction of the terahertz constitutive tensors of multilayer graphene-dielectric stacks

摘要： In this paper, we present a reliable method to extract the electromagnetic constitutive tensors of complex synthesized multilayer graphene-dielectric stacks in the terahertz band. This macroscopic electromagnetic characterization method uses the transmission and reflection coefficients of a normal-incident circularly polarized electromagnetic wave on the material structure. The employment of circularly polarized waves has the advantage of overcoming the ambiguity at high frequencies attributed to the multi-branching discontinuities in the extracted permeability and permittivity tensors of natural or synthesized materials. The retrieved permeability and permittivity tensors are validated by the data obtained from analytical and numerical solutions of the original electromagnetic problem for the case of circularly polarized wave incidence.