Indirectly coupled films

A positive coupling has been observed between magnetic films separated by a thin metallic layer. Five methods which have been developed for measuring this coupling and the variation of the coupling with evaporation temperature, measuring temperature, and thickness of the intermediate layer are described. Three mechanisms are proposed for the observed coupling : bulk diffusion of ferromagnetic atoms into the intermediate layer, diffusion of magnetic atoms along grain boundaries, and polarization of conduction electrons. The effect of this coupling on slow switching, pulse switching, and creep is discussed.