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arXiv · 2001.07928

Bulk superconductivity induced by Se substitution in self-doped BiCh2-based compound CeOBiS2-xSex

Ryosuke Kiyama·Yosuke Goto·Kazuhisa Hoshi·Rajveer Jha·Akira Miura·Chikako Moriyoshi·Yoshihiro Kuroiwa·Tatsuma D. Matsuda·Yuji Aoki·Yoshikazu Mizuguchi
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Abstract

We report the Se substitution effects on the crystal structure, superconducting properties, and valence states of self-doped BiCh2-based compound CeOBiS2-xSex. Polycrystalline CeOBiS2-xSex samples with x = 0-1.0 were synthesized. For x = 0.4 and 0.6, bulk superconducting transitions with a large shielding volume fraction were observed in magnetic susceptibility measurements; the highest transition temperature (Tc) was 3.0 K for x = 0.6. A superconductivity phase diagram of CeOBiS2-xSex was established based on Tc estimated from the electrical resistivity and magnetization measurements. The emergence of superconductivity in CeOBiS2-xSex was explained with two essential parameters of in-plane chemical pressure and carrier concentration, which systematically changed with increasing Se concentration.

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Ryosuke Kiyama, Yosuke Goto, Kazuhisa Hoshi, Rajveer Jha, Akira Miura, Chikako Moriyoshi, Yoshihiro Kuroiwa, Tatsuma D. Matsuda, Yuji Aoki, Yoshikazu Mizuguchi. 2020-01-22. Bulk superconductivity induced by Se substitution in self-doped BiCh2-based compound CeOBiS2-xSex. https://doi.org/10.7566/jpsj.89.064702

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