在高压下,铁基超导体 Nd(O0.88F0.12) FeAs 的结构稳定性和可压缩性
Jinggeng Zhao1, Luhong Wang, Dawei Dong
1Natural Science Research Center, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, China.
Journal of the American Chemical Society
|September 27, 2008
概括
高压实验显示,基于铁的超导体Nd(O0.88F0.12) FeAs的同结构相位过渡约为10 GPa. 这种过渡改变了结构参数,并显著增加了散装模块.
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:
- 基于铁的超导体,如 Nd(O0.88F0.12) FeAs,是具有独特电子性质的关键材料类.
- 了解它们在极端条件下的行为,如高压,对于基础科学和潜在应用至关重要.
研究的目的:
- 为了研究 Nd(O0.88F0.12) FeAs 对施加压力的结构反应.
- 确定相位过渡行为及其对材料结构和弹性性能的影响.
主要方法:
- 在高压角度分散式X射线衍射实验中,在室温下进行了高达32.7GPa的X射线衍射实验.
- 瑞特维尔德精炼方法用于详细的结构分析.
主要成果:
- 观察到一个异构的相位过渡,从大约10 GPa开始.
- 在13.5GPa以上,一个独特的高压阶段出现,在同一四角形结构内有一个更大的a轴和更小的c轴.
- 环境条件异热散装模 (B0) 确定为低压阶段的102(2) GPa和高压阶段的245(9) GPa.
- 在两个阶段之间确定了结合距离和角度的压力依赖的差异.
结论:
- Nd(O0.88F0.12) FeAs在高压下经历了显著的结构转变,导致格子参数发生变化和刚度增加.
- 观察到的同结构过渡和随后的相变更为铁基超导体中压力诱导的电子和结构相关性提供了洞察力.
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