Noise- and force-induced resonances in noisy rotary oscillations of classical spins.

As an important example of noisy rotary oscillations, the dynamic magnetization of an assembly of superparamagnetic particles is considered. In the presence of a bias field, there exists a mechanism that causes selective suppression of higher harmonics in the response spectrum of the system. Manifestation of this effect at temperature variation is known as the noise-induced resonance. Its manifestation at the change of excitation intensity, formerly unknown, we term the force-induced resonance.