Four fold in-plane magnetic anisotropy in sputtered (100)MgO/Fe epitaxial films

We report structural and magnetic properties of Fe thin films, deposited onto (100)MgO substrates by rf magnetron sputtering. The successful epitaxial growth of Fe<100>(100) parallel to MgO<110>(100) was achieved at a practical growth rate of 0.73 nm/s. The M-H hysteresis measured along Fe<100> directions exhibits a superior squareness with a low coercivity (H_c = 5 Oe). The saturation field along <110> directions, exceeding 500 Oe, demonstrates the crystalline cubic anisotropy comparable to the bulk Fe. The anisotropic properties of the initial susceptibility against an oscillation field of 1 mOe amplitude were also confirmed with inductive measurements.