Interface Effects on Magnetic and Magneto-Optical Properties in TbFeCo/Pt Multilayers

The present paper discusses the effect of Pt on the magnetic and magneto-optical properties in TbFeCo/Pt multilayer films fabricated by sputter-deposition, in conjunction with interfacial structures. Both the magnetic and magneto-optical properties as a function of Pt thickness are reasonably well explained on the basis of a model in which an interfacial region very similar to an Fe-Pt alloy is assumed. Furthermore, low angle X-ray diffraction analysis and polar Kerr magneto-optical spectra simulation over a photon energy range from 1.4 to 6.8 eV (wavelength λ = 182 to 886 nm) reveal that the Fe-Pt alloy-like interfacial regions are formed only on top of TbFeCo layers, but not on Pt layers. A possible contribution of polarized Pt atoms to the magneto-optical spectra is also discussed.