Effect of Zn impurity on the pressure dependence of superconducting transition temperature T-c in YBa2Cu3-xZnxO7-delta single crystals

We report ac susceptibility measurement of the superconducting transition temperature T-c under hydrostatic pressure P up to 12 kbar, on a series of Zn-substituted YBa2Cu3-xZnxO7-delta single-crystal samples. Our results show that introducing Zn impurities systematically enhances the pressure dependence of T-c, but the absolute value of dT(c)/dP remains small, despite that the T-c drops greatly. The results seem to demonstrate that band effect is not involved in the dramatic depression of T-c upon Zn substitution.