In-plane chemical pressure essential for superconductivity in BiCh2-based (Ch: S, Se) layered structure

Yoshikazu Mizuguchi; Akira Miura; Joe Kajitani; Takafumi Hiroi; Osuke Miura; Kiyoharu Tadanaga; Nobuhiro Kumada; Eisuke Magome; Chikako Moriyoshi; Yoshihiro Kuroiwa

doi:10.1038/srep14968

arXiv · 1504.01208

In-plane chemical pressure essential for superconductivity in BiCh2-based (Ch: S, Se) layered structure

Yoshikazu Mizuguchi·Akira Miura·Joe Kajitani·Takafumi Hiroi·Osuke Miura·Kiyoharu Tadanaga·Nobuhiro Kumada·Eisuke Magome·Chikako Moriyoshi·Yoshihiro Kuroiwa

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Abstract

BiCh2-based superconductors (Ch: S, Se) are a new series of layered superconductor. However, mechanisms for the emergence of superconductivity in BiCh2-based superconductors have not been clarified. In this study, we have investigated crystal structure of two series of optimally-doped BiCh2-based superconductors, Ce1-xNdxO0.5F0.5BiS2 and LaO0.5F0.5Bi(S1-ySey)2, using powder synchrotron x-ray diffraction in order to reveal the relationship between crystal structure and superconducting properties of the BiCh2-based family. We have found that an enhancement of in-plane chemical pressure would commonly induce bulk superconductivity in both systems. Furthermore, we have revealed that superconducting transition temperature for REO0.5F0.5BiCh2 superconductors could universally be determined by degree of in-plane chemical pressure.

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Yoshikazu Mizuguchi, Akira Miura, Joe Kajitani, Takafumi Hiroi, Osuke Miura, Kiyoharu Tadanaga, Nobuhiro Kumada, Eisuke Magome, Chikako Moriyoshi, Yoshihiro Kuroiwa. 2015-04-06. In-plane chemical pressure essential for superconductivity in BiCh2-based (Ch: S, Se) layered structure. https://doi.org/10.1038/srep14968

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