Ferromagnetic resonance studies of noble metals based sandwiches

In this paper we have prepared Fe/Cu, Ag, Au/Fe sandwiches by ion beam sputtering and studied the interlayer coupling behavior by ferromagnetic resonance technique. In these sandwiches the Fe and noble metal layers are polycrystalline in the textures of (110) and (111), respectively. It is found that the in-plane resonance field and the linewidth oscillate as a function of nonmagnetic layer thickness in a period of about 1.0 nm for Fe/Cu, Au/Fe structures, and 1.4 nm for Fe/Ag/Fe system. It is suggested that the interlayer coupling strength between the ferromagnetic layers oscillates in the same period with the resonance field. An in-plane anisotropy was found in Fe/Ag/Fe system.