Conduction-Electron Spin Density around Fe Impurities in Cu above and belowTK

Abstract

The nuclear resonances of five shells of Cu atoms that are near neighbors to single Fe atoms in dilute alloys of CuFe were observed. The resonance positions show that the conduction-electron spin polarization oscillates with distance from the Fe impurity. Four of the resonances from 300 deg K to well below the 29 deg K Kondo temperature were followed finding that, for all four, the spin density has the same temperature dependence as the magnetic susceptibility. These data show that, contrary to some speculation, there is no drastic change in the spatial polarization associated with the Kondo condensation.'' (auth)