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arXiv · 2103.16064

Disappearance and Survival of Superconductivity in FeSe under High Pressure

Kiyotaka Miyoshi·Shota Yamamoto·Atsushi Shiota·Takuya Matsuoka·Masaki Ohe·Yumi Yamamoto·Shijo Nishigori
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Abstract

Superconductivity in FeSe was investigated under high pressure through the measurements of DC magnetization by using a diamond anvil cell. We successfully observed that the disappearance of the superconductivity as a results of the appearance of the non-superconducting ortho I\hspace{-1pt}I phase above $\sim$7 GPa ($\sim$5 GPa), when Ar (glycerin) is used as the pressure transmitting media. Contrary to this, it has been found that the superconductivity even survives under pressure above 7 GPa, when the thickness ($t$) of a platelet-single crystal specimen is reduced. The survival of the superconductivity above 7 GPa is consistent with a previous observation under hydrostatic pressure by using a cubic anvil apparatus, suggesting that the hydrostaticity of the pressure is improved by reducing $t$. It is also inferred that the appearance of the ortho I\hspace{-1pt}I phase is due to uniaxial stress along the [001] direction.

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Kiyotaka Miyoshi, Shota Yamamoto, Atsushi Shiota, Takuya Matsuoka, Masaki Ohe, Yumi Yamamoto, Shijo Nishigori. 2021-03-30. Disappearance and Survival of Superconductivity in FeSe under High Pressure. https://doi.org/10.7566/jpsj.90.073706

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