Albuquerque, Eudenilson Lins deMedeiros, Fábio Ferreira de2014-12-172007-04-032014-12-172004-12-03MEDEIROS, Fábio Ferreira de. Polaritons de exciton em super-redes semicondutoras. 2004. 99 f. Dissertação (Mestrado em Física da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera) - Universidade Federal do Rio Grande do Norte, Natal, 2004.https://repositorio.ufrn.br/jspui/handle/123456789/16644In this work we study the spectrum (bulk and surface modes) of exciton-polaritons in infinite and semi-infinite binary superlattices (such as, ···ABABA···), where the semiconductor medium (A), whose dielectric function depends on the frequency and the wavevector, alternating with a standard dielectric medium B. Here the medium A will be modeled by a nitride III-V semiconductor whose main characteristic is a wide-direct energy gap Eg. In particular, we consider the numerical values of gallium nitride (GaN) with a crystal structure wurtzite type. The transfer-matrix formalism is used to find the exciton-polariton dispersion relation. The results are obtained for both s (TE mode: transverse electric) and p (TM mode: transverse magnetic) polarizations, using three diferent kind of additional boundary conditions (ABC1, 2 e 3) besides the standard Maxwell's boundary conditions. Moreover, we investigate the behavior of the exciton-polariton modes for diferent ratios of the thickness of the two alternating materials forming the superlattice. The spectrums shows a confinement of the exciton-polariton modes due to the geometry of the superlattice. The method of Attenuated Total Reflection (ATR) and Raman scattering are the most adequate for probing this excitationsapplication/pdfAcesso AbertoExciton de FrenkelExciton de Wannier-MottPolaritons de exciton (PE)Super-redes quasiperiódicasFormalismo da matriz de transferênciaCálculo da relação de dispersão dos PEs e nitretosExciton of frenkelExciton of wannier-mottExciton-polaritonTransfer-matrix formalismExciton-polariton dispersion relationNitridemasterThesisCNPQ::CIENCIAS EXATAS E DA TERRA::FISICA