9 research outputs found
Simple trace criterion for classification of multilayers
The action of any lossless multilayer is described by a transfer matrix that
can be factorized in terms of three basic matrices. We introduce a simple trace
criterion that classifies multilayers in three classes with properties closely
related with one (and only one) of these three basic matrices.Comment: To be published in Optics Letter
Optimizing omnidirectional reflection by multilayer mirrors
Periodic layered media can reflect strongly for all incident angles and
polarizations in a given frequency range. Quarter-wave stacks at normal
incidence are commonplace in the design of such omnidirectional reflectors. We
discuss alternative design criteria to optimize these systems.Comment: 9 pages, 6 figures. To be published in J. Opt. A: Pure and Applied
Optic
Design of electron band pass filters for electrically biased finite superlattices
We design optimal band pass filters for electrons in semiconductor heterostructures, under a uniform applied electric field. The inner cells are chosen to provide a desired transmission window. The outer cells are then designed to transform purely incoming or outgoing waves into Bloch states of the inner cells. The transfer matrix is interpreted as a conformal mapping in the complex plane, which allows us to write constraints on the outer cell parameters, from which physically useful values can be obtained