Propriedades espectrais de super-redes fotônicas formadas por metamateriais

Abstract

In this thesis, we had studied the transmissivity of electromagnetic waves in onedimensional photonic structures composed by metamaterials in many ways. Applying the formalism of transfer matrix, comparing the transmission spectra between two systems: defective photonic superlattices composed of subwavelength slab widths and a simple photonic structures formed by three layers. Through the effective medium theory, with good accuracy, we had shown the equivalence of the above systems in the spectral region in which there are modes of resonant tunneling for both structures. Furthermore, we had derived a general condition which should be satisfied to observe the resonant modes. Our analytical results may be useful from a technological point of view to propitiate, in the design and development of photonic devices, adjustment or selection of resonant frequencies. Finally, we investigated the electromagnetic wave transmission properties through a multilayer system consisting of alternated layers of air and uniaxially anisotropic metamaterials. The optical axis of each heterostructure coincides with the direction of stacking of the layers. The components of the electric permittivity and magnetic permeability tensors that characterize the metamaterial are modeled by a Drude-type response and split-ring resonator metamaterial response, respectively. Different plasmon frequencies are considered for directions perpendicular and parallel to the optical axis. For oblique incidence, longitudinal plasmon polariton modes are found in the neighborhood of the plasmon frequency along the optical axis. The anisotropy leads to unfolding of nearly dispersionless plasmon-polariton bands either above or below the plasmon frequency. Moreover, it is shown that, even in the presence of loss /absorption, these plasmon polariton modes do survive and, therefore, should be experimentally detected.