Magneto-optical longitudinal Kerr effect in a film-substrate system

Abstract

The problem of electromagnetic reflection at an arbitrary angle of incidence in a system consisting of an isotropic ambient, a magnetic film and a thick magnetic substrate is considered. The magnetization in both the film and substrate is assumed parallel to the planar interfaces and to the plane of incidence. The analysis provides the dispersion relation for the guided wave propagation in the system. The obtained general formulae are applied to the special cases of (a) normal incidence, (b) oblique incidence on a uniaxial film on a uniaxial substrate, both optical axes being parallel to the interfaces and to the plane of incidence, and (c) to the case when the permittivity tensor diagonal elements are the same and the off-diagonal element is small. The possible practical applications of the present analysis are in the ellipsometry of thin-film — substrate structures displaying magnetic order and in the theory of magneto-optic thin-film devices for integrated optics.