RADIATION-INDUCED T-C REDUCTION AND PAIR-BREAKING IN HIGH-T-C SUPERCONDUCTORS

The radiation-induced reduction of the transition temperature in several high- Tc superconductors is quantitatively compared to the predictions of pair breaking theory for magnetic defects in isotropic superconductors and nonmagnetic defects in anisotropic superconductors. In all cases the reduction in Tc is consistent with theory if Cu and O vacancies in the CuO2 planes are pair breaking. Copper plane site vacancies appear to scatter charge carriers twice as effectively as O site vacancies. Scattering potentials are found to be comparable to magnetic scattering potentials in conventional superconductors. © 1995 The American Physical Society.