Magneto-optical properties of Fe-B-F films

Films have been preprared by sputtering over a wide range of compositions in the Fe-B-F system. Fluorine was supplied by rf sputtering from an FeF3 target, and Fe-B by dc sputtering from arc-melted targets. Most of the samples were amorphous, although some contained a relatively small fraction of crystalline FeF2. The films were ferromagnetic, with Curie temperatures above room temperature and with room-temperature saturation magnetizations of 60 to 150 emu/g. Large Faraday coefficients, up to 105 deg/cm at 633 nm and fairly large Kerr rotations were observed.