HIGH-PRESSURE AND TRANSPORT-PROPERTIES ON SOME HIGH-T-C SUPERCONDUCTORS

By analyzing the pressure effects on the resistivity (rho) of some hig h temperature superconductors, we have found a strong correlation betw een the normal state rho and the superconducting transition temperatur e (T-c). Experimental data show that when pressure reduces the normal state rho, T-c increases; when pressure enhances rho, T-c decreases. O ur experimental data can be explained in terms of the parabolic T-c-n (carrier concentration) function, suggesting that the pressure-induced variation of rho arises from the change in n.