Intrinsic Phase Diagram of Superconductivity in the BiCh2-based System Without In-plane Disorder

Kouhei Nagasaka; Atsuhiro Nishida; Rajveer Jha; Joe Kajitani; Osuke Miura; Ryuji Higashinaka; Tatsuma D. Matsuda; Yuji Aoki; Akira Miura; Chikako Moriyoshi; Yoshihiro Kuroiwa; Hidetomo Usui; Kazuhiko Kuroki; Yoshikazu Mizuguchi

doi:10.7566/jpsj.86.074701

arXiv · 1702.07485

Intrinsic Phase Diagram of Superconductivity in the BiCh2-based System Without In-plane Disorder

Kouhei Nagasaka·Atsuhiro Nishida·Rajveer Jha·Joe Kajitani·Osuke Miura·Ryuji Higashinaka·Tatsuma D. Matsuda·Yuji Aoki·Akira Miura·Chikako Moriyoshi·Yoshihiro Kuroiwa·Hidetomo Usui·Kazuhiko Kuroki·Yoshikazu Mizuguchi

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Abstract

We have investigated the crystal structure and physical properties of LaO1-xFxBiSSe to reveal the intrinsic superconductivity phase diagram of the BiCh2-based layered compound family. From synchrotron X-ray diffraction and Rietveld refinements with anisotropic displacement parameters, we clearly found that the in-plane disorder in the BiSSe layer was fully suppressed for all x. In LaO1-xFxBiSSe, metallic conductivity and superconductivity are suddenly induced by electron doping even at x = 0.05 and 0.1 with a monoclinic structure. In addition, x (F concentration) dependence of the transition temperature (Tc) for x = 0.2-0.5 with a tetragonal structure shows an anomalously flat phase diagram. With these experimental facts, we have proposed the intrinsic phase diagram of the ideal BiCh2-based superconductors with less in-plane disorder.

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Kouhei Nagasaka, Atsuhiro Nishida, Rajveer Jha, Joe Kajitani, Osuke Miura, Ryuji Higashinaka, Tatsuma D. Matsuda, Yuji Aoki, Akira Miura, Chikako Moriyoshi, Yoshihiro Kuroiwa, Hidetomo Usui, Kazuhiko Kuroki, Yoshikazu Mizuguchi. 2017-02-24. Intrinsic Phase Diagram of Superconductivity in the BiCh2-based System Without In-plane Disorder. https://doi.org/10.7566/jpsj.86.074701

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