Effect of3dImpurities on the Superconducting Transition Temperature of the Layered Compound NbSe2

Abstract
The transition temperature of NbSe2 as a function of the concentration of such paramagnetic impurities as Fe, Ni, and Co shows a very strong anomaly close to the critical concentration which destroys superconductivity. The strength of the effect in NbSe2 is believed to be caused both by the weak depairing of the impurities and by their nonstatistical distribution resulting from the layered structure.