Theory of Magnetic Anisotropy of Rare Earth Impurities in Gadolinium Metal

抄録

Magnetic anisotropy due to a few percent of rare earth impurities (Ce∼Tm) in gadolinium metal is studied theoretically by use of a formalism developed in a previous paper. A correction for finite concentration of impurities is carried out to the results calculated on the single impurity system. A single ion type anisotropy is adopted as an origin of the anisotropy of the impurity spin. Fairly good reproductions of torque curves measured by Tajima and Chikazumi are obtained for impurities of the heavy rare earth elements with microscopic anisotropy constants not differing very much from those expected by the usual crystal field theory, whereas for the light ones the status is less satisfactory.