Exchange anisotropy in NiFe films on (100) NiO single-crystal substrate

The exchange anisotropy in a Ni81Fe19 film sputtered on a (100) NiO single-crystal substrate is investigated with MOKE magnetometry, ferromagnetic resonance (FMR) and Brillouin light scattering (BLS). The dependencies of the spin-wave frequency and FMR resonance field with the angle of the in-plane field are strikingly different than in polycrystalline samples. The BLS and FMR data are interpreted with a model that includes a planar domain wall in the AF substrate while the exchange field in the single-crystal sample is quite larger than in NiFe films on polycrystalline NiO layers, the domain wall field is smaller. (C) 2001 Elsevier Science B.V. All rights reserved.