在BaFe2的结构和超导过渡上方的电子阴性性 (As(1-x) P(x)) 2
S Kasahara1, H J Shi, K Hashimoto
1Department of Physics, Kyoto University, Kyoto 606-8502, Japan.
Nature
|June 23, 2012
概括
铁超导体中的电子阴性在结构过渡温度以上出现,并延伸到超导阶段. 这挑战了以前的假设,并揭示了新的假设.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 超导电性 超导电性 超导电性
背景情况:
- 电子阴性,一种破坏旋转对称性的状态,在铁和铜氧化物中观察到,但其在每一种中的作用是有争议的.
- 在铁类动物中,阴性性通常与四角形到正角形结构过渡 (Ts) 相关.
- 之前的阴性性研究仅限于突破C(4) 对称性的相,使其在Ts以上的存在未得到证实.
研究的目的:
- 为了研究铁体在结构过渡温度以上的电子阴性质的存在和行为.
- 为了澄清铁基超导体中阴性,结构过渡和超导性之间的关系.
- 为了比较铁 pnictides 的 nematic 相图与氧化铜超导体的相图.
主要方法:
- 在同等配系统的磁力扭矩测量BaFe(2)(As(1-x) P(x))(2).
- 同步光X射线衍射测量. 同步光X射线衍射测量.
- 分析相位转换和对称性破坏.
主要成果:
- 电子阴性在结构过渡温度 (Ts) 以上发展,并持续到超导体制.
- 鉴定出一个明显的阴性过渡温度 (T*),发生在Ts以上.
- 在Ts的结构过渡被重新归类为"元脑学过渡",而不是真正的相位过渡.
结论:
- 铁虫的性是一种比以前想象的更基本的特性,存在于结构过渡的独立性.
- 铁酸的阴性相图与氧化铜的伪间隙相图有相似之处.
- 这项研究提供了对高温超导体中阴性,结构和超导性相互作用的关键见解.
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