Ferromagnetic resonance in a single-domain particle with uniaxial anisotropy under longitudinal excitation

An additional resonance peak near the effective anisotropy field $H_{\mathrm{KN}}$ is identified on the basis of analysis of magnetization precession dynamics of single-domain uniaxial magnetic ellipsoid particle in the spectrum of ferromagnetic resonance, corresponding to bias along the “hard” axis, under longitudinal excitation by a weak high-frequency field. This peak is related to manifestation of the angular bistability arising due-to the presence of two symmetrical angular equilibrium positions of particle magnetization in a field that is weaker than the $H_{\mathrm{KN}}$ field.