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arXiv · 1511.09005

Optical Study of BaFe$_2$As$_2$ under pressure: Coexistence of spin-density-wave gap and superconductivity

E. Uykur·T. Kobayashi·W. Hirata·S. Miyasaka·S. Tajima·C. A. Kuntscher
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Abstract

Temperature-dependent reflectivity measurements in the frequency range 85 - 7000 cm$^{-1}$ were performed on BaFe$_2$As$_2$ single crystals under pressure up to $\sim$5 GPa. The corresponding pressure- and temperature-dependent optical conductivity was analyzed with the Drude-Lorentz model to extract the coherent and incoherent contributions. The gradual suppression of the spin-density wave (SDW) state with increasing pressure and the appearance of the superconducting phase coexisting with the SDW phase at 3.6~GPa were observed. At 3.6~GPa, the reflectivity reaches unity below $\sim$95~cm$^{-1}$ indicating the opening of the superconducting gap and shows a full gap tendency at 6 K.

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E. Uykur, T. Kobayashi, W. Hirata, S. Miyasaka, S. Tajima, C. A. Kuntscher. 2015-11-29. Optical Study of BaFe$_2$As$_2$ under pressure: Coexistence of spin-density-wave gap and superconductivity. https://doi.org/10.1103/physrevb.92.245133

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