It is known that the structure of a Co-Cr base alloy film consists of a Co base ferromagnetic phase in grains and a Cr base paramagnetic phase in the neighborhood of the grain boundary. It has been reported that this structure is caused by a miscibility gap due to magnetic transformation. The miscibility gap due to magnetic transformation in the Co-Cr binary system has already been calculated by the CALPHAD method. However, the miscibility gap due to the magnetic transformation in a B-added Co-Cr base alloy has not yet been calculated. In this paper, the effect of B-addition on the miscibility gap in a Co-Cr base alloy is calculated by the CALPHAD method.
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.