Power reflection and transmission coefficients for a chiral slab and meander-line polarizer with chiral slab

ABSTRACT POWER REFLECTION AND TRANSMISSION COEFFICIENTS FOR A CHIRAL SLAB AND MEANDER -LINE POLARIZER WITH CHIRAL SLAB DELİHACIO?LU Kemal M. S. in Electrical and Electronics Engineering Supervisor: Asst. Prof. Dr. Savaş UÇKUN November 1998, 97 pages In this study, the power reflection and transmission coefficients have been analyzed for TE and TM incident plane waves on a chiral slab and meander -line polarizer with chiral slab. In the analysis of chiral slab without meander-line polarizer, the electric and magnetic fields are written in terms of the modal fields for a linearly polarized and circularly polarized fields in air and chiral regions, respectively. In the chiral region the electric and magnetic fields are expressed as the sum of left circularly polarized (LCP) and right circularly polarized (RCP) plane waves whereas in the air region a linearly polarized TE or TM wave is assumed and incident on a chiral slab. The derivation of power reflection mand transmission coefficients are realized in a straightforward manner after matching the tangential components of the electric and magnetic fields at the boundaries. Since at the boundary tangential components of the electric and magnetic fields are continuous. For a meander-line polarizer with chiral slab, the fields are derived in modal form both in air and chiral regions. Meander-line strip is placed periodically in the xy plane. It is assumed to be infinitely thin and conducting perfectly. Due to the periodicity of the problem the fields are expanded into Floquet modes in the air and chiral regions. The boundary conditions combined with the orthogonality of the Floquet modes over a single periodic unit cell, lead to an integral equation for the unknown current density, induced on the metallic part of the meander-line by the incident plane wave. This integral equation can be solved by using the moment method by expanding the unknown current density in terms of a set of basis functions and testing with the same basis. The solution of the resulting matrix equations is carried out by the complex matrix inversion program. The power reflection and transmission coefficients can easily be found from the electric field equations by using the Poynting vector. As a result, the power reflection and transmission coefficients have been plotted with respect to frequency and incident angle for different values of chirality admittance, slab thickness, and relative permittivity of the chiral medium. Keywords : Meander - line, chiral IV