In-plane chemical pressure essential for superconductivity in BiCh2-based (Ch: S, Se) layered structure.
In-plane chemical pressure essential for superconductivity in BiCh2-based (Ch: S, Se) layered structure.
复制标题
面内化学压力对基于 BiCh2（Ch：S，Se）的层状结构的超导性至关重要。
DOI：
10.1038/srep14968
复制
发表时间：
2015-10-08
影响因子：
4.6
通讯作者：
Kuroiwa Y
中科院分区：
文献类型：
--
作者：
Mizuguchi Y;Miura A;Kajitani J;Hiroi T;Miura O;Tadanaga K;Kumada N;Magome E;Moriyoshi C;Kuroiwa Y
基于BiCh 2的化合物（Ch：S，Se）是一系列新的层状超导体，这些材料中出现超导电性的机制尚未阐明。在这项研究中，我们研究了BiCh 2基超导体家族的晶体结构和超导性能之间的关系，特别是最佳掺杂的Ce 1 −xNdxO0.5F0.5BiS2和LaO0.5F0.5Bi（S1−ySey）2。我们使用粉末同步辐射X射线衍射来确定晶体结构。我们发现，在这两个系统中出现体超导电性必不可少的结构参数是面内化学压力，而不是Bi-Ch键长或面内Ch-Bi-Ch键角。此外，我们表明，所有的REO 0.5F0.5BiCh2超导体的超导转变温度可以确定从面内化学压力。
BiCh2-based compounds (Ch: S, Se) are a new series of layered superconductors, and the mechanisms for the emergence of superconductivity in these materials have not yet been elucidated. In this study, we investigate the relationship between crystal structure and superconducting properties of the BiCh2-based superconductor family, specifically, optimally doped Ce1−xNdxO0.5F0.5BiS2 and LaO0.5F0.5Bi(S1−ySey)2. We use powder synchrotron X-ray diffraction to determine the crystal structures. We show that the structure parameter essential for the emergence of bulk superconductivity in both systems is the in-plane chemical pressure, rather than Bi-Ch bond lengths or in-plane Ch-Bi-Ch bond angle. Furthermore, we show that the superconducting transition temperature for all REO0.5F0.5BiCh2 superconductors can be determined from the in-plane chemical pressure.