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arXiv · 2003.12800

Superconductivity in the nonsymmorphic line-nodal compound CaSb$_2$

Atsutoshi Ikeda·Mayo Kawaguchi·Shun Koibuchi·Tatsuki Hashimoto·Takuto Kawakami·Shingo Yonezawa·Masatoshi Sato·Yoshiteru Maeno
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Abstract

We found superconductivity in CaSb$_2$ with the transition temperature of 1.7 K by means of electrical-resistivity, magnetic-susceptibility, and specific-heat measurements. This material crystallizes in a nonsymmorphic structure and is predicted to have multiple Dirac nodal lines in the bulk electronic band structure protected by symmetry even in the presence of spin-orbit coupling. We discuss a possible topological superconductivity for the quasi-2-dimensional band originating mainly from one of the antimony sites.

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Atsutoshi Ikeda, Mayo Kawaguchi, Shun Koibuchi, Tatsuki Hashimoto, Takuto Kawakami, Shingo Yonezawa, Masatoshi Sato, Yoshiteru Maeno. 2020-03-28. Superconductivity in the nonsymmorphic line-nodal compound CaSb$_2$. https://doi.org/10.1103/physrevmaterials.4.041801

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