Metamalzeme yapılarda dalga yayınımı ve homojenleştirme parametrelerinin elde edilmesi

Wave Propagation in Metamaterial Structures andRetrieval of Homogenization ParametersErdinç IrcıAbstractElectromagnetic wave propagation in metamaterial structures is investigated. Scatteredand transmitted electromagnetic fields by these structures due to electric line sources orplane wave illuminations are found. A generic formulation of these wave propagationproblems is done, enabling any kind of metamaterial or conventional material to be used,having any sign combination of constitutive parameters and having any electric and/ormagnetic losses.For metamaterial coated conducting cylinders illuminated normally with plane waves,achieving transparency and maximizing scattering are investigated thoroughly. It is foundout that, rigorous derivation of transparency and resonance (scattering maximization)conditions for PEC core cylinder case under the sub-wavelength limitations yields thesame conditions of two electrically small concentric layers of conjugately pairedcylinders, (when the inner core layer is also taken to the PEC limit). The relationsbetween the permittivity of the coating and the ratio of core-shell radii are investigatedfor achieving transparency and scattering maximization.A novel homogenization method for the retrieval of effective constitutive parameters ofmetamaterials is proposed and implemented. While implementing the method, 1, 2, …,20 unit cells of the same metamaterial structure are stacked and their reflectioncoefficients are collected. The homogenization quality of the metamaterial is evaluated interms of various factors, which showed that the method is very successful.Finally, another method has been proposed for the retrieval of surface wave propagationconstants on any periodic or non-periodic grounded slab medium. As a preliminary, themethod is applied to grounded dielectric slabs.