Af. Isakovic et al., Control of magnetic anisotropy in Fe1-xCox films on vicinal GaAs and Sc1-yEryAs surfaces, J APPL PHYS, 89(11), 2001, pp. 6674-6676
We demonstrate that two distinct surface contributions to the magnetocrysta
lline anisotropy can be used to control the magnetic properties of thin fil
ms of bcc Fe1-xCox grown on GaAs (100) and Sc1-yEryAs (100). The bare GaAs
(100) surface has twofold symmetry, and Fe1-xCox films grown directly on it
show a strong uniaxial magnetic anisotropy. Fourfold symmetry is restored
in films grown on interlayers of Sc1-yEryAs, in which the rock-salt structu
re provides a fourfold symmetric surface. A uniaxial magnetic anisotropy ca
n be induced in this case by miscutting the substrate towards a {111} plane
, so that vicinal steps run along a [011] direction. A simple Neel pair-bon
ding model describes the evolution of the anisotropy with the degree of mis
cut. For miscut GaAs (100) surfaces without interlayers, both the intrinsic
anisotropy originating from the surface bonding and a step-induced term co
ntribute to the total magnetic anisotropy. Depending on the orientation of
the miscut, the step contribution can either enhance or partially suppress
the intrinsic uniaxial anisotropy. (C) 2001 American Institute of Physics.