Magneto-optical characteristics of SiN/GdFe films

The magneto-optical and optical properties of GdFe single layer films, whic h are covered with a thin Si3N4 layer, were studied in the visible waveleng th region. A Kerr rotation peak and a reflectivity drop were observed near 4.1 eV in GdFe alloyed films and attributed to the Gd element. Compared wit h the single thick GdFe film, the Kerr effect of SiN/GdFe bilayers was enha nced, due to the optical interference between Si3N4 and GdFe. The Kerr rota tion of GdFe films showed a nonlinear function of the compositions in the w hole measured wavelength range. Magneto-optical measurements directly evide nce the spin-flip in the GdFe films as the Gd content increased from 20.7 t o 24.2 at. %, which showed advantages over conventional magnetometry. (C) 2 001 American Institute of Physics.