Large induced magnetic anisotropy in manganese spinel ferrite films

The oxygen pressure dependence of magnetic anisotropy in pulse laser deposited manganese ferrite (MnFe2O4) 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(O2)< 8 mTorr) or perpendicular to it (p(O2)>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. (C) 2005 American Institute of Physics.