First Investigation of Pressure Effects on Transition from Superconductive to Metallic Phase in FeSe0.5Te0.5

High-pressure resistivity experiments were performed on FeSe0.5Te0.5. The onset temperature of T, (T-c(onset)) increases rapidly from 13.5 to 26.2K upon applying pressure up to 2GPa. Above 2GPa, T-c decreases linearly and the metallic phase was observed at P = 14GPa. The same relationship between normalized T-c and pressure in both FeSe0.5Te0.5 and FeSe suggests a universal pressure dependence in this system. This report presents the first observation of a phase transition from the Superconducting to the metallic phase on the P-T-c phase diagram.