We have grown single-crystal Co ferrite (CoFe2O4) on MgO(001) by oxygen-plasma-assisted molecular beam epitaxy (OPA-MBE), and have characterized the composition, structure, surface morphology, and magnetic properties by a number of methods The as-grown OPA-MBE material forms a perfect inverse spinel, in which all Co is in the ?² formal oxidation state, and occupies octahedral sites within the cation sublattice. The OPA-MBE film surfaces are very flat, with mean roughnesses of only a few A, and exhibit large, stable magnetic domains. The measured moment per unit volume is 250 emu/cm3, and the saturation magnetization for films in the 1000A film thickness range is ~60% of that of bulk Co ferrite. The material also exhibits strain-dependent magnetic anisotropy that can be understood by considering the various contributions to the total magnetic energy. The overall quality of epitaxial Co ferrite grown on MgO by OPA-MBE is superior in every respect to that obtained using pulsed laser deposition as the growth method.
Revised: March 17, 2004 |
Published: April 1, 2002
Citation
Chambers S.A., R.F. Farrow, S. Maat, M. Toney, L. Folks, J.G. Catalano, and T.P. Trainor, et al. 2002.Molecular Beam Epitaxial Growth and Properties of CoFe2O4 on MgO(001).Journal of Magnetism and Magnetic Materials 246, no. 1-2:124-139.PNNL-SA-35010.