On the broadening of the linewidth in the spin-wave spectra of single crystal nickel films

Abstract

The ferromagnetic resonance technique has been used to study the broadening of the linewidth of the main resonance mode in the spin-wave spectra of single crystal nickel films. All the resonance experiments were performed at about 17 GHz, at room temperature. An expression for the angular dependence of the effective linewidth, Δ H e, is obtained and used in the analysis of the experimental results. The calculated ΔD e indicates a strong dependence on the angle between the applied magnetic field and the normal to the film surface. In addition, ΔH e is always larger in the parallel orientation than in the perpendicular orientation. A mechanism is suggested for the broadening of the linewidth measured at oblique angles together with evidence for two-magnon scattering.