Interband mixing and induced local-moment - Conduction-band spin distributions

The spin distribution induced in free-electron-like conduction bands by local (rare-earth) electronic magnetic moments has been investigated quantitatively. Both interband mixing effects and the more familiar Ruderman - Kittel - Kasuya - Yosida exchange-polarization terms have been accounted for. The former include (1) effective exchange^1,2 terms, arising from the interband mixing, which contribute to both the average induced spin density and its spatial distribution; and (2) direct interband admixture terms¹ which affect only the spatial distribution (and affect neither the average density nor the density at the origin of the impurity moment). The results are found to be sensitive to the conduction electron Fermi wave vector k _F: in some cases, the admixture terms have little effect on the spin distribution outside of the impurity site; in others, they produce spin-density oscillations which are large in amplitude compared with the RKKY result.