Stochastic magnetic resonance of absorption effects of surface morphology in thin film magnetics

The effect of surface roughness in thin film magnetics on magnetic susceptibility and Dynamic Magnetic Hysteresis (DMH) loops are investigated using Brown's continuous diffusion of magnetic spins model. The magnetic relaxation time of the magnetic thin films is determined by regressing the two-mode approximation for the magnetic susceptibility onto experimental data obtained for Ni₄₅Fe₅₅. There is a moderate linear correlation between the magnetic relaxation time and the surface roughness to the thickness (SRT) ratio. The area of the DMH loops and the non-linear dynamic magnetic susceptibility strongly depend on the magnetic relaxation time and the SRT of the films. The thin films exhibit a strong linear relationship between the coercivity and the SRT ratio, along with a strong logarithmic dependence of the dynamic magnetic susceptibility on the SRT ratio.