Effect of Pressure on Superconducting Transition Temperatures in the Bi-Sr-Ca-Cu-O System

Abstract
Superconducting transition temperatures were measured under pressure for the Bi-Sr-Ca-Cu-O system. The transition temperature near 80 K (T c1) slightly increases with pressure: dT c1/dp=0.06 K/GPa (onset), while T c near 110 K (T c2) decreases with pressure: dT c2/dp=-0.2 K/GPa (onset) and -0.3 K/GPa (complete). The negative pressure-dependence was discussed with regard to the resonating-valence-bond theory.