Magneto-Optical and Magnetic Properties of Co-Substituted BaM

BaM(BaFe12O19) has strong crystal anisotropy, but its Faraday rotation is low at only 0.22 deg/¿m (¿= 780 nm). An attempt to improve the properties of this material as magneto-optical recording media by replacing part of the Fe in BaM with Co is discussed. It was found that ¿F increased with the amount of Co substituted. The investigation confirmed that Co is effective in increasing BaM ¿F. When La is used for Co charge compensation, along with increasing ¿F, it was also found that the crystal anisotropy becomes high, and the properties of the material as magneto-optical recording media improved.