Zero-resistance superconducting phase in BaFe2 As2 under high pressure

A single-crystalline sample of BaFe2 As2 was prepared by high-pressure synthesis, and temperature dependence of resistivity was measured under high pressures of up to 9.0 GPa. Application of 3.0 GPa pressure suppresses the spin-density wave transition and induces superconductivity with the zero resistance state at a superconducting transition temperature Tc =35 K. Tc decreases monotonically with increasing pressure. The appearance of the superconductivity and the disappearance of the anomaly due to the spin-density wave transition occur simultaneously at a pressure of 3.0 GPa. At 3.0 GPa, a superconducting transition is induced in BaFe2 As2; however, the superconductivity is suppressed at higher pressure.