Investigation of a one-dimensional magnetophotonic crystal for the study of ultrathin magnetic layer

We investigated one dimensional magnetophotonic crystals consisting of a cavity containing a magnetic layer between two Bragg reflectors. This structure can be made very efficient to obtain a localized mode with enhanced Faraday rotation. In this paper, the parameters of the magnetic layer (thickness and position within the cavity) were systematically varied in order to find theoretically the most efficient structure according to a figure-of-merit. A significant enhancement of the Faraday rotation, θF, by a factor of twelve is found compared with a single cobalt layer. Our calculations show the possibility of using this huge enhancement for ultrathin magnetic layer studies. The experimental spectrum of the ellipsometric parameter tan(Ψ) agrees with the calculated results.