GHz permeability of soft CoZr films: The role of exchange–conductivity coupling

Abstract The microwave permeability of CoZr films with different thicknesses is investigated. While Landau–Lifschitz model accounts for the response of the thinnest samples, several peaks are observed on the permeability of thicker layers. A simple model commonly used to account for the permeability of layers in the presence of skin effect is compared to a more sophisticate model taking into account the exchange–conduction coupling. Both models are found to be equivalent. They fail to account for the observed high frequency peaks. Introducing pinning conditions at the interface reproduces qualitatively observed behavior, suggesting the presence of standing spinwaves.