Km. Krishnan et al., MAGNETISM AND MAGNETIZATION STRUCTURE OF C-AXIS ORIENTED SINGLE-CRYSTAL COBALT FILMS GROWN EPITAXIALLY ON RIGID UNDERLAYERS, Journal of applied physics, 75(11), 1994, pp. 7579-7581
c-axis oriented, single-crystal, Co films were grown on mica using eit
her Ti or Ru underlayers and exhibited the following crystallographic
orientation relationship (00.1)mica \\ (00.1)underlayer \\ (00.1)Co, a
nd [11.0]mica \\ [10.0]underlayer \\ [10.0]Co. Fundamental magnetic pr
operties of the films were measured: H(c) approximately 4 Ka/m, B(s) a
pproximately 1.95 T, and K(u) approximately 5 X 10(5) J/m3 . The as-gr
own magnetization structure of thinner (t less-than-or-equal-to 30 nm)
films shows mainly 180-degrees domain walls with a uniform distributi
on of crossties, while thicker (t=60 nm) samples show stripe domains w
ith a width of 75 nm. In spite of their excellent c-axis orientation (
FWHM(Co(002)) approximately 1.5-degrees), the effective anisotropy of
these films is in-plane but with a small perpendicular magnetization c
omponent. These features in the hysteresis behavior are consistent wit
h a simple noninteracting particle model incorporating the shape aniso
tropy of the small sized grains. For thinner samples the validity of t
his model has been verified by annealing experiments.