Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Ultrathin Fe films exhibit an excellent epitaxial relation to MgO(100) substrates because of a very low lattice mismatch (~3.8%). Due to a cubic symmetry of the Fe crystal an in-plane fourfold magnetic anisotropy is induced. By means of ion erosion coherently aligned single crystalline patterns (ripples) are created at the MgO surface, which induce an additional uniaxial magnetic anisotropy in the afterwards deposited Fe film. The uniaxial magnetic anisotropy direction and strength is controlled by an arbitrarily chosen irradiation direction with respect to the sample plane and the ion energy dependent ripple wavelength, respectively. Thus an ensemble of twofold and fourfold anisotropy is created and analyzed by ferromagnetic resonance and magneto-optic Kerr effect techniques. Theoretical analysis reveals both the anisotropy fields and their directions that are in a perfect agreement with the experiment.