Observation of a well characterized 180 degrees domain wall by polarized neutron reflectometry

In a GdFe (500 Angstrom)/TbFe(50 Angstrom) amorphous sample, a 180 degrees magnetic domain wall (DW) can be created in the soft GdFe magnetic layer an d be pinned by the hard TbFe layer. The modulation vector of the Bloch DW i s perpendicular to the film plane and the magnetization lays in plane. Usin g different amplitude of the applied magnetic field, we can control the wid th of the DW at the interface between GdFe and TbFe. The polarized neutron reflectivity measurements in the presence of a DW exhibits a clear discrepa ncy with the reflectivity measured in the saturated state. The influence of the DW thickness is observed. These results are confirmed by simulation. ( C) 2000 Elsevier Science B.V. All rights reserved.