在SmFeAsO1-xFx中在43K的超导率
1Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China. chenxh@ustc.edu.cn
Nature
|May 27, 2008
概括
研究人员发现了一种新的基于铁的超导体,SmFeAsO{1-x) F{x),在43K时表现出超导性.这一发现超过了以前的非氧化铜记录,为高温超导性研究提供了新的途径.
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
- 固态化学 固态化学
背景情况:
- 高过渡温度 (高-T(c)) 超导性主要在铜氧化物中观察到.
- 理论上的最大T (c) 约为40K,而MgB (b) 则在39K处保持非氧化铜记录.
- 层层的稀土金属氧基化物 (LnOFeAs) 正成为一种新的超导体.
研究的目的:
- 为了探索超导性超出铜氧化物之外的高T (c) 超导性新材料.
- 为了研究SmFeAsO(1-x) F(x) 的ZrCuSiAs型结构中的超导性.
- 建立一个新的材料平台,以了解高温超导的机制.
主要方法:
- 合成和描述具有ZrCuSiAs类型结构的SmFeAsO{1-x) F{x).
- 电阻测量以确定超导过渡温度 (T) (c).
- 对磁感应度的测量,以确认散装超导.
主要成果:
- 在SmFeAsO ((1-x) F ((x)) 中发现了散装超导性.
- 达到高达43K的超导过渡温度 (T(c)) .
- 这一T (c) 超过了非氧化铜超导体的先前记录.
结论:
- SmFeAsO{1-x) F{x) 代表了非氧化铜超导性的重大进步.
- 这种新材料为对高T (c) 超导的起源进行基础研究提供了有价值的系统.
- 这一发现扩大了用于探索超导现象的材料的范围.
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