Superconducting properties of ion implantedIn Mn alloys

Annealed Indium films have been implanted with 150 keV-Mn ions at low temperatures. TheT_c-depression and the low temperature part of the resistivity exhibit the Kondo effect, the Kondo temperature being strongly influenced by lattice defects. The lattice disorder has been increased by pre-implantation of In ions. The influence of lattice disorder on the magnetic properties ofIn Mn alloys is explained by applying the strong coupling theory of superconductors.It is found that the main effect results from a shift of the Fermi energy relative to the virtual bound state, due to a variation of the effective massm₀·(1+).