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.
@article{arxiv.2001.07928,
title = {Bulk superconductivity induced by Se substitution in self-doped BiCh2-based compound CeOBiS2-xSex},
author = {Ryosuke Kiyama and Yosuke Goto and Kazuhisa Hoshi and Rajveer Jha and Akira Miura and Chikako Moriyoshi and Yoshihiro Kuroiwa and Tatsuma D. Matsuda and Yuji Aoki and Yoshikazu Mizuguchi},
journal= {arXiv preprint arXiv:2001.07928},
year = {2020}
}