Critical temperature modification of low dimensional superconductors by spin doping

Ion implantation of Fe and Mn into Al thin films was used for effective modification of Al superconductive properties. The critical temperature of the transition to the superconducting state was found to decrease gradually with implanted Fe concentration. It was found that suppression by Mn implantation is much stronger compared to Fe. At low concentrations of implanted ions, suppression of the critical temperature can be described with reasonable accuracy by existing models, while at concentrations above 0.1 at.% a pronounced discrepancy between the models and experiments is observed.