A single-crystalline sample of ${\text{BaFe}}_2{\text{As}}_2$ 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 $T_c=35\text{K}$. $T_c$ 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 ${\text{BaFe}}_2{\text{As}}_2$; however, the superconductivity is suppressed at higher pressure.

• Received 21 February 2009

DOI:https://doi.org/10.1103/PhysRevB.79.172506