Initial magnetization, remanence, and coercivity of the random anisotropy amorphous ferromagnet

We analyze the coercivity, remanence, and initial magnetization of a single-domain, single-component amorphous material. We assume a uniform ferromagnetic exchange and concentrate on the effect of single-ion anisotropy. We find a threshold anisotropy below which the coercivity is zero. At large anisotropy, the coercivity is proportional to the anisotropy energy. Exchange pulling increases the remanence of amorphous materials. We suggest that exchange pulling between crystallites may also be operative in small-grain metallic polycrystals.