Fig. 7

Polarized neutron reflectivity (PNR) measurements. Specular neutron reflectivity patterns (solid symbols) along with their best fits (open symbols) as a function of Qz for the non-spin flip (NSF) [R−− (black) and R++ (red)] and spin flip (SF) [R+− (blue) and R−+ (green)] channels measured at a coercive field Ha = −10.0 kOe (–1000 mT) after field cooled (FC) and measured at 10 K for the [Dy10/Tb10]10 sample. Error bars represent standard error of the estimated intensity. The simulations are done using models considering cases a without any 2π-domain wall and b with 2π-domain walls in both layers of Dy and Tb. Shown alongside are the nuclear (ρn) and magnetic (ρm) scattering length densities (SLDs) versus thickness of the multilayer