Effect of Electron Irradiation on Superconductivity in Single Crystals of Ba(Fe1−xRux)2As2 (x = 0.24)
Résumé
A single crystal of isovalently substituted BaðFe1−xRuxÞ2As2 (x = 0.24) is sequentially irradiated with2.5 MeV electrons up to a maximum dose of 2.1 × 10^19 e−=cm2. The electrical resistivity is measuredin situ at T =22 K during the irradiation and ex situ as a function of temperature between subsequentirradiation runs. Upon irradiation, the superconducting transition temperature Tc decreases and the residualresistivity ρ0 increases. We find that electron irradiation leads to the fastest suppression of Tc comparedto other types of artificially introduced disorder, probably due to the strong short-range potential of thepointlike irradiation defects. A more detailed analysis within a multiband scenario with variable scatteringpotential strength shows that the observed Tc versus ρ0 is fully compatible with s+/-pairing, in contrast to earlier claims that this model leads to a too rapid suppression of Tc with scattering.