在以铁为基础的分层化合物LaO(1-x) F(x) FeAs中的43K超导率
Hiroki Takahashi1, Kazumi Igawa, Kazunobu Arii
1Department of Physics, College of Humanities and Sciences, Nihon University, Sakurajosui, Setagaya-ku, Tokyo 156-8550, Japan. hiroki@chs.nihon-u.ac.jp
Nature
|April 25, 2008
概括
施加压力给添加的LaOFeAs超导体显著提高了它们的临界温度 (T(c)). 这项研究突出了铁氧基化物作为一个有前途的新平台,用于高温超导体的发现.
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:
- 像LaOFeP和LaONiP这样的基于铁和的分层化合物表现出低温超导性.
- 在LaOFeAs (LaO{1-x}F{x}FeAs) 中的化物兴奋剂增加了其超导过渡温度 (T{c}) 至大约26K.
- 这些材料的超导性通常与磁性不稳定性有关,其中T (c) 受载体兴奋剂和电荷转移的影响.
研究的目的:
- 为了研究外部压力对化LaOFeAs的超导过渡温度 (T(c)) 的影响.
- 探索分层铁氧尼基的潜力,作为实现更高超导过渡温度的材料平台.
主要方法:
- 对用添加的LaOFeAs样品进行外部压力的实验应用.
- 在不同压力条件下测量超导过渡温度 (T(c)).
- 分析铁氧尼克特的压力,电荷转移和超导之间的关系.
主要成果:
- 增加的压力导致F-doped LaOFeAs的发病T (c) 急剧增加.
- 在大约4GPa时,达到大约43K的最大T(c).
- 这代表了迄今为止报告的最高T (c) 值之一,不包括基于铜的高T (c) 超导体.
结论:
- 外部压力显著增强了化LaOFeAs的超导性.
- 亚的压缩性和增强的电荷转移有助于压力诱导的T (c) 增加.
- 层状铁氧化物 (LnOTMPn) 为发现新的高温超导体提供了一个有前途的材料平台.
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