OPTIMIZATION AND ENHANCEMENT OF TRANSITION-TEMPERATURE FOR HGBA2CA2CU3O8+DELTA CERAMIC SUPERCONDUCTORS

To control and optimize the superconductivity critical temperature T-c of Hg-based superconductor is not only important for applications, bu t also useful for providing possible explanations for the mechanism of high T-c superconductivity. In the present work, we successfully obta ined a T-c(R=0) (zero-resistance temperature) = 135 K, T-c(dia) (diama gnetic onset temperature) = 143 K, an optimum hole concentration p(0) = 0.22 and the T-c-p phase diagram for the HgBa2Ca2Cu3O8+delta superco nductors with substitution of Hg by Pb.