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arXiv · 0904.4631

Effect of Uniaxial Stress for Pressure-Induced Superconductor SrFe_2As_2

H. Kotegawa·T. Kawazoe·H. Sugawara·K. Murata·H. Tou
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Abstract

We report that the pressure-temperature phase diagram of single-crystalline SrFe$_2$As$_2$ is easily affected by the hydrostaticity of a pressure-transmitting medium. For all of the three mediums we used, superconductivity with zero resistance appears, accompanied by the suppression of an antiferromagnetic (orthorhombic) phase, but the critical pressure $P_c$ was found to depend on the type of medium. $P_c$ was estimated to be 4.4 GPa under almost hydrostatic condition, but it decreased to $3.4-3.7$ GPa with the use of the medium already solidified at room temperature. The uniaxial stress along the c-axis is suggested to aid in the suppression of the antiferromagnetic (orthorhombic) phase. The pressure effect of BaFe$_2$As$_2$ is also reported.

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H. Kotegawa, T. Kawazoe, H. Sugawara, K. Murata, H. Tou. 2009-06-17. Effect of Uniaxial Stress for Pressure-Induced Superconductor SrFe_2As_2. https://doi.org/10.1143/jpsj.78.083702

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