Figure 5
Results for the two-dimensional Fourier components , , , CT = and for the total magnetic SANS cross section [(48)] using expression (40). The upper row shows the results taking into account only the zero-order term in (40), which corresponds to the case of a homogeneously magnetized particle. The lower row displays the results when the second-order term (ν = 1) in (40) is taken into account. The parameters are eA = ez, b0 = 0.1ez (B0 ≃ 48 mT), kc = 0.1, ks = 3 and m0 = [sinβcosα, sinβsinα, cosβ]. Note that υy and υz denote the dimensionless components of the scattering vector [compare equation (34)]. Since the Néel surface anisotropy effectively has a cubic symmetry (see Fig. 1), we average over the angles α = (45°, 135°, 225°, 315°) and β = 20°. A logarithmic colour scale is used. |