Finite-temperature behavior of anisotropic two-sublattice magnets

The finite-temperature magnetism of rare-earth transition-metal intermetall ics is investigated by extending the n-component vector spin model to two-s ublattice magnets. Mean-field analysis shows that the influence of the rare -earth anisotropy on the mean-field Curie temperature is much smaller than expected from the low-temperature rare-earth anisotropy. The use of ultrasp herical polynomials yields a generalization of the famous m(m+1)/2 power-la w exponent to m(m+n-2)/(n-1). (C) 1998 American Institute of Physics. [S002 1-8979(98)48811-X].