We have calculated the FMR line shape for magnetic multilayer structures of alternating iron and iron-alloy layers. The model assumes abrupt interfaces and that spins on adjacent layers are ferromagnetically coupled with an exchange constant $A_{12}$. The surface magnetic anisotropy fields are set to zero in our calculations. As $A_{12}$ is increased, satellite lines in the surface impedance split off from the ferromagnetic resonance main lines of the component materials. The number of satellites is one more than the number of layered pairs. The position and strength of these lines is found to be dependent on the relative layer thicknesses as well as the interlayer exchange coupling.

• Received 17 April 1987

DOI:https://doi.org/10.1103/PhysRevB.36.8574