Magneto-optical properties of ferromagnetic/nonferromagnetic interfaces: Application to Co/Au(111)

An approach is proposed to give a reliable description of the ferromagnetic/nonferromagnetic interface contributions to magneto-optical (MO) Kerr effect. We show that well chosen magneto-optical parameters related to the interfaces and extracted from the experimental data are independent on the angle of incidence and the polarization of the incident light. They are also invariant with respect to the optical properties and thicknesses of sandwiching layers. The method was tested on the Au/Co/Au(111) system. It was found that the assumptions and predictions of the theoretical description agree with the experimental observations. Further analysis of the experimental data shows indirectly that a significant part of the MO interface-induced effects are coming from the electronic hybridization at Au/Co interfaces. Consequently, the data could be a useful source of information for ab initio calculations of the layer-resolved permittivity tensor.