Domain structure in FeCoTiZr multilayers analysed from 3D neutron depolarisation

3-D polarisation analysis is performed in the neutron beam transmitted at g lancing angles 0 < \omega\ < 5 degrees through a multilayer 60(FeCo/TiZr) o n an Si substrate. Samples were used with various thicknesses up to 30 nm o f the TiZr layers at a constant thickness of 10 nm of the FeCo layers. Also , measurements were taken at constant omega in a number of orientations as the sample was rotated in its own plane (psi-scans). These scans show a 360 degrees rather than a 180 degrees period. The magnetisation direction of t he domains is analysed. From the combined omega- and psi-scans a domain str ucture is deduced consisting of overlapping slab domains inclined by a few degrees to the sample plane. Their thickness includes several FeCo/TiZr bil ayers; their in-plane dimensions are up to 10 mu m. This suggests a magneti c coupling (possibly of dipolar origin) between the CoFe layers over a non- magnetic interlayer of thickness up to 30 nm. (C) 1999 Elsevier Science B.V . All rights reserved.