Superconducting gap symmetry of the BiS$_2$-based superconductor LaO$_{0.5}$F$_{0.5}$BiSSe elucidated through specific heat measurement

Naoki Kase; Yusuke Terui; Tomohito Nakano; Naoya Takeda

doi:10.1103/physrevb.96.214506

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arXiv · 1709.05992

Superconducting gap symmetry of the BiS$_2$-based superconductor LaO$_{0.5}$F$_{0.5}$BiSSe elucidated through specific heat measurement

Naoki Kase·Yusuke Terui·Tomohito Nakano·Naoya Takeda

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Abstract

In this study, the superconducting gap symmetry of LaO$_{0.5}$F$_{0.5}$BiSSe is elucidated through specific heat measurements with one single crystal of LaO$_{0.5}$F$_{0.5}$BiSSe. A clear jump is observed at 3.95 K in LaO$_{0.5}$F$_{0.5}$BiSSe, suggesting bulk superconductivity. From specific heat measurements, $ΔC_\mathrm{e}/γT_\mathrm{c}$ and 2$Δ$(0)/$k_\mathrm{B}T_\mathrm{c}$ are obtained as 2.31 and 4.5. These values indicate strong electron-phonon coupling superconductivity. The temperature ($T$) and magnetic-field ($H$) dependence of the electronic specific heat $C_\mathrm{e}(T, H)$ suggests that superconductivity is fully gapped. Our handmade system successfully elucidates superconducting gap symmetry of the BiS$_2$-based compound with a small single crystal.

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Naoki Kase, Yusuke Terui, Tomohito Nakano, Naoya Takeda. 2018-01-10. Superconducting gap symmetry of the BiS$_2$-based superconductor LaO$_{0.5}$F$_{0.5}$BiSSe elucidated through specific heat measurement. https://doi.org/10.1103/physrevb.96.214506

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