FMR STUDIES OF FE BILAYERS AND MULTILAYERS (AG/FE)N - EVIDENCE FOR A DYNAMIC INTER-MAGNETIC LAYER COUPLING

The FMR spectrum, at X band and room temperature, is studied as a function of the dc field orientation for a series of films constituted of (Ag\Fe bilayer\Ag) sandwiches where the Fe bilayers (Fe1\Ag\Fe2) have the same Fe layer thickness (36 angstrom) but a Ag spacer thickness varied in a large range. All the resonance characteristics of these Fe bilayers, when compared to the ones of a Fe single layer control sample, provide evidence for dynamic coupling effects between the two Fe layers which, we suggest, are to be associated with the diffusion of the conduction electron magnetization through the Ag spacer.