IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Magnetic Interfaces and Nanostructures Thursday Sessions
       Session MI-ThP

Paper MI-ThP13
Non-monotonic Magnetic Surface Anisotropy of Epitaxial Fe Films Grown on Vicinal Substrates

Thursday, November 1, 2001, 5:30 pm, Room 134/135

Session: Magnetic Thin Films & Surfaces Poster Session
Presenter: M. Rickart, University Kaiserslautern, Germany
Authors: S.O. Demokritov, University Kaiserslautern, Germany
M. Rickart, University Kaiserslautern, Germany
J. Jorzick, University Kaiserslautern, Germany
B. Hillebrands, University Kaiserslautern, Germany
Correspondent: Click to Email
The presented work is devoted to the study of the influence of atomic steps at the interface between a magnetic film and a substrate on the magnetic surface anisotropy of the film. Step induced anisotropy contributions appear because of the broken translational invariance perpendicular to the steps. The Fe films were prepared on vicinal MgO(001) substrates with Ag(001) and Au(001) buffers using a molecular beam epitaxy UHV system. Substrates with two different miscut orientations (along [100] and [110]) were used. In-situ characterization was performed by LEED, RHEED and SPM, and chemical analysis by Auger electron spectroscopy. Magnetic anisotropy contributions have been determined from the hysteresis loops and from frequencies of spin waves measured by Brillouin light scattering. In addition to the four-fold anisotropy intrinsic for (001) Fe films the vicinal films demonstrate an uniaxial anisotropy. The strength of the uniaxial anisotropy depends on the miscut angle, the miscut orientation, and the buffer material. Fe films prepared on Au buffers with the miscut orientation along the [100]-direction show an additional uniaxial anisotropy with the easy axis perpendicular to the steps. For the Fe films prepared on Au buffers with the miscut orientation along the [110]-direction a non-monotonic dependence of the anisotropy strength as a function of the miscut angle is observed: the orientation of the magnetic easy axis switches from parallel to perpendicular to the steps, crossing zero value between 1.5 and 2 degrees of the miscut angle. Fe films prepared on Ag buffers with the miscut orientation along the [100] direction shows the same orientation of the uniaxial anisotropy easy axis, as those prepared on Au, however the anisotropy strength is much higher than that observed on Fe/Au system. The properties of the observed uniaxial anisotropies are analyzed on the basis of the Neel pair-bonding model.