Analysis of the approximation to saturation magnetization and dynamics of demagnetization of PrDyFeCoB amorphous spin glass

An analysis of the field and time dependencies of the magnetization of PrDyFeCoB amorphous crystalline microwires is presented. It is found that the magnetization curve near the saturation field has a smoother approximation to saturation than in a ferromagnet, according to theoretical predictions for the spin-glass state of the alloy in the amorphous state within the framework of the random magnetic anisotropy model. Deviations of the dynamics of relaxation of the magnetization of microwires from the logarithmic time dependence and the disappearance of this difference when observing magnetic relaxation in a magnetic field are found. This indicates the typical dynamics of the magnetization reversal of a spin glass in a zero field and the ferromagnetic character of demagnetization in a nonzero field. The results indicate the presence in the PrDyFeCoB microwires of an exotic magnetic state of the material with stochastic local magnetic anisotropy.