Nonlinear ferromagnetic resonance in anisotropic ferrite ellipsoid

The nonlinear equation of motion of the magnetization vector in an anisotropic ferrite ellipsoid is solved by the N. N. Bogolyubov averaging method [1]. It is shown that in the case of uniform precession with a frequency $\omega$ there can exist subharmonic and multiple resonances with frequencies $\omega\simeq\nu/q$ ($q=1,2,3,4,5$) and $\omega\simeq 2\nu$, where $\nu$ is the uhf field frequency.