J. Valentin et al., MICROMAGNETIC ANALYSIS OF MAGNETIZATION REVERSAL IN COPT ALLOY-FILMS, Journal of physics. D, Applied physics, 29(5), 1996, pp. 1111-1115
We have studied the magnetization reversal processes in polycrystallin
e CoPt magneto-optic recording alloys with perpendicular magnetic anis
otropy. Thin films of composition Co28Pt72 with total thicknesses in t
he range 5 nm to 30 nm were investigated with Kerr contrast imaging. D
epending on the film deposition parameters we find domain wall motion
or domain nucleation dominated processes. Numerical simulations of the
magnetization reversal processes were carried out within a two-dimens
ional array model of interacting mesoscopic single domain particles. I
ncluding dipolar fields and domain wall contributions, we find that th
e demagnetizing fields dominate the reversal mechanisms and strongly a
ffect the shape of the hysteresis loops. Additional microstructural an
alysis reveals that the typical grain sizes of the (111) textured poly
crystalline alloy films are of the order of about 20 nm which coincide
s with the typical cell size representing a single domain particle in
the micromagnetic numerical simulations.