Analysis of Ferromagnetic Resonance Linewidth in Ni Thin Film Fabricated by Electrodeposition Method

We obtained resonance field (H-res) and linewidth (Delta H-PP) from measured ferromagnetic resonance signal in the functions of polar angle (theta(H)) in Ni thin film of 240 nm thickness fabricated by electrodeposition method. The angular dependence of H-res was well fitted with the calculated ones. We confirmed that the g-factor and effective demagnetization field were 2.18 and 445 emu/cc by the theoretical analysis of the resonance field, respectively. The angular dependence of Delta H-PP showed very large values at in-plane direction (theta(H)=90 degrees), which could not explained by the homogenous linewidth due to the Gilbert damping and inhomogeneous linewidth due to the angular variations and magnetization variations by the surface layer. Therefore, we considered the spin wave scattering (two magnon scattering) process in order to analyze the measured inhomogeneous linewidth, which was appeared in thicker film than the critical thickness of 50 nm. The defect medicated spin wave scattering played a key role in the electrodoposited Ni thin film of 240 nm thickness.