A THEORETICAL INVESTIGATION OF THE EFFECT OF THE OBLIQUE ANISOTROPY AXIS ON THE FERROMAGNETIC RESONANCE LINEWIDTH

The effect of the oblique anisotropy axis on the ferromagnetic resonance (FMR) linewidth in a thin film is studied theoretically. The angular dependence of the frequency linewidth is investigated in the plane containing the anisotropy axis and in the film plane. The effect of the tilt angle on the frequency linewidth is shown. Some unusual broadening of the lines in the FMR spectra and certain features of the variation of the frequency linewidth Δf with field orientation and field intensity could be interpreted as being due to the fact that the magnetocrystalline anisotropy axis, i.e., the easy or hard direction of the magnetization, is tilted from the normal with an angle δ. The tilt angle δ as well as the Gilbert damping coefficient α can be deduced from experimental data through this analysis.