Superconductivity in YBa2−xSrxCu3O7−δ

Abstract
We report structure, resistivity, and Meissner effect measurements on YBa2−xSrxCu3O7−δ for 0<xx=1.0 and a monotonic depression of Tc with x. Using arguments based on structural changes with Sr doping, we speculate that the depression of Tc is due to the local distortion of the lattice in the neighborhood of the Sr site and the introduction of additional oxygen vacancies.