Perpendicular magnetic anisotropy in CoFe2O4(001) films epitaxially grown on MgO(001)

Abstract

We report on the magnetic properties of epitaxial cobalt-ferrite films with orientations parallel to [001] and [111] grown by a reactive molecular beam epitaxy method using pure ozone gas as an oxidation agent. Both Mssbauer spectroscopy and magnetization measurement of the CoFe 2 O 4 (001) film grown on MgO(001) indicate that the film has perpendicular magnetic anisotropy (PMA) with high coercivity, whereas the film of CoFe 2 O 4 (111) grown on α-Al2O3(0001) appears to be paramagnetic. The maximum uniaxial anisotropy energy for CoFe 2 O 4 (001) estimated from the magnetization and coercivity at room temperature is ≈ 3 10 6 erg/cm 3. © 2011 American Institute of Physics.