Pressure dependence of the superconducting critical temperature of the Tl0.5Pb0.5Sr2Ca1-xYxCu2O7 system (original) (raw)

Using a cryogenic diamond anvil cell the pressure dependence of the superconducting transition temperature T c of Tl 0.5 Pb 0.5 Sr 2 Ca 1Ϫx Y x Cu 2 O 7 for xϭ0.0, 0.1, 0.2, and 0.35 has been measured resistively up to ϳ20 GPa. In high-T c superconductors there are two contributions to the pressure dependence of T c : one related to pressure-induced charge transfer and one due to intrinsic effects. In the present experiment these contributions could be separated using a simple phenomenological model which incorporates the effect of changes in both the yttrium content x and the applied pressure p on T c . In this system it is found that there hardly is any charge transfer by pressure so that the intrinsic pressure effect is the main contribution to ‫ץ‬T c /‫ץ‬p. The maximum T c which can be reached in this system is 112 K.