Measurements of the longitudinal magnetooptic kerr reflection of a simple multilayer structure

The longitudinal magnetooptic Kerr reflection of simple multilayer structures consisting of 4 layers and less were measured at a wavelength of λ = 6328 Å and compared with theory. The agreement is good, considering the dependence of the complex index of refraction of the Fe films on thickness. The films were evaporated in a vacuum of 10-5torr. The best results were obtained with the combination ZnS-Fe-MgF2-Ag. For an appropriate thickness of the iron film we measured a value of Kerr reflection, 4 times greater than that of opaque material coated with one dereflection layer of ZnS. This comparitively simple structure showed nearly the same results as the structure of 13 layers proposed by Keay and Lissberger. Replacing the ZnS layer by a perfect dielectric matching stack, the Kerr reflection could theoretically be additionally increased four times, thus obtaining the results otherwise given by a 22-layer structure.