Effect of electron irradiation and Pr doping on the charge transport in YBCO single crystals

The influence of irradiation by electrons with energies of 0.5 ... 2.5 MeV at temperatures of about 10 K on the basal-plane resistivity of the YBa2Cu3O7-delta single crystals is investigated in the range from T-c to 300 K. The resistivity temperature dependence is determined by defects arising due to the irradiation. These defects directly affect the superconducting transition, decreasing T-c and increasing the transition width without significant distortions of its shape. The resulting defects also lead to an increase in the Debye temperature due to a reduction of the anisotropy, and a noticeable increase in the scattering by phonons in the sample. The excess conductivity does not change with the irradiation used.