Large induced magnetic anisotropy in manganese spinel ferrite films

The oxygen pressure dependence of magnetic anisotropy in pulse laser deposited manganese ferrite ( Mn Fe 2 O 4 ) films was investigated. Magnetic anisotropy fields ( H a ) are shown to exceed 5 kOe when films were processed at oxygen pressures below 5 mTorr . Further, it is shown that the magnetically preferred direction of H a can be aligned either along the film plane ( p O 2 < 8 mTorr ) or perpendicular to it ( p O 2 > 8 mTorr ) . The ability to induce large perpendicular magnetic anisotropy in spinel ferrites allows for new applications (i.e., phase shifters, filters, isolators, and circulators) near or above X -band frequencies to be considered.