Polaritons em materiais magnéticos nanoestruturados

In this work we present a theoretical study about the properties of magnetic polaritons in superlattices arranged in a periodic and quasiperiodic fashíons. In the periodic superlattice, in order to describe the behavior of the bulk and surface modes an effective medium approach, was used that simpli...

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Detalles Bibliográficos
Autor: Araújo, Carlos Alexandre Amaral
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Institución:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:portugués
OAI Identifier:oai:repositorio.ufrn.br:123456789/16662
Acceso en línea:https://repositorio.ufrn.br/jspui/handle/123456789/16662
Access Level:acceso abierto
Palabra clave:Polaritons
Quase-cristais
Super-rede
Metamagnetos
Fibonacci
Quasi-crystals
Superlattice
Metamagnets
CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
Descripción
Sumario:In this work we present a theoretical study about the properties of magnetic polaritons in superlattices arranged in a periodic and quasiperiodic fashíons. In the periodic superlattice, in order to describe the behavior of the bulk and surface modes an effective medium approach, was used that simplify enormously the algebra involved. The quasi-periodic superlattice was described by a suitable theoretical model based on a transfer-matrix treatment, to derive the polariton's dispersion relation, using Maxwell's equations (including effect of retardation). Here, we find a fractal spectra characterized by a power law for the distribution of the energy bandwidths. The localization and scaling behavior of the quasiperiodic structure were studied for a geometry where the wave vector and the external applied magnetic field are in the same plane (Voigt geometry). Numerical results are presented for the ferromagnet Fe and for the metamagnets FeBr2 and FeCl2