Propriedades de transmissão de ondas eletromagnéticas em multicamadas dielétricas com desordem diluídas

Abstract

In this work we study some aspects of the transmission of an electromagnetic wave inciding normally on a multilayer film with diluted disorder, which consists of a substrate composed of layers of refractive index nA and thickness dA occupying the sublattice with an odd index and random layers in the even sublattice. The even layers will be considered to have refractive index n_A with probability p or refractive index nB with probability p -1, satisfying the Bragg condition ( nAdA= nBdB ). Applying the transfer matrix formalism we compute the transmission spectrum, the reduced Lyapunov coefficient and the scaling behaviour of the frequency average transmission as a function of the system size. We observed the absence of the quarter-wavelengh ressonance observed in the disordered binary multilayer. As a consequence of this, the scaling behaviour of the frequency average transmission exhibts an exponential decay as the total size of the stack increases. We also investigate the dependence of the frequency average transmission with the probability p for a fixed system size. Our results suggests that the disorder introduced by the variable p in the dielectric structure can potentially be used in the development of wide-band filters.