Spin-orbit-induced magnetic anisotropy for impurities in metallic samples. II. Finite-size dependence in the Kondo resistivity

The electrical resistivity, including the Kondo resistivity increase at low temperature, is calculated for thin films of dilute magnetic alloys. Assuming that in the nonmagnetic host the spin-orbit interaction is strong like in Au and Cu, the magnetic impurities have a surface anisotropy calculated in paper I. That anisotropy hinders the motion of the spin. Including that anisotropy, the effective electron-impurity coupling is calculated by using the second-order renormalization-group equations. The amplitude of the Kondo resistivity contribution is reduced as the position of the impurity approaches the surface, but the increase occurs approximately at the bulk Kondo temperature. Different proximity effects are also explained qualitatively, where the films of magnetic alloys are covered by pure second films with different mean free path. The theory explains the experimental results in those cases, where a considerable amount of impurities is at the surface inside the ballistic region.