Magnetic induction and domain walls in magnetic thin films at remanence

Abstract

Magnetic domain walls in thin films can be well analysed using polarized neutronreflectometry. Well defined streaks in the off-specular spin-flip scattering maps areexplained by neutron refraction at perpendicular Néel walls. The position of the streaksdepends only on the magnetic induction within the domains, whereas the intensity of theoff-specular magnetic scattering depends on the spin-flip probability at the domain wallsand on the average size of the magnetic domains. This effect is fundamentally different andhas to be clearly distinguished from diffuse scattering originating from the size distributionof magnetic domains. Polarized neutron reflectivity experiments were carried out using a3He gas spin filter with a analysing power as high as 96% and a neutron transmissionof approximately 35%. Furthermore, the off-specular magnetic scattering wasenhanced by using neutron resonance and neutron standing wave techniques.