Skomski, R.
Spin-glass permanent magnets
Journal of Magnetism and Magnetic Materials 157-158, pp 713-714 (1996)
The ground state of random-anisotropy permanent magnets, such as isotropic nanostructured Sm2Fe17N3, is investigated. The degeneracy of the ground-state of strongly disordered random-anisotropy magnets leads to finite-range ferromagnetic ground-state correlations and ferromagnetic configurations whose energies are comparable to the ground-state energy. This explains why the coercivity of typical rare-earth containing random-anisotropy spin glasses exceeds that of industrial ceramic magnets by more than one order of magnitude. By comparison, random-field spin glasses are unsuitable for permanent magnetic applications.
ki-1996-s02