Magnetic anisotropy and interlayer exchange coupling in the sputtered Co/Ag multilayers

The in‐plane uniaxial anisotropy and perpendicular anisotropy of sputtered Co/Ag(111) multilayers have been investigated by magnetic measurements and the in‐plane ferromagnetic resonance (FMR) technique. The data‐fitting analysis for the FMR experimental results about the angular dependence of the resonance field shows that the in‐plane anisotropy cannot be fully described by only using the first‐order term, and the second‐order term must be included. Furthermore, the interface‐induced anisotropy has been obtained by FMR. Both ferromagnetic and antiferromagnetic couplings have been revealed by hysteresis loop measurement. Specifically, a spin‐flip phase transition has been observed in the sputtered Co/Ag(111) multilayers, which is attributed to the effects of the AF‐coupling and in‐plane uniaxial anisotropy.