在Cs ((3) C ((60) 中,超导和磁性的多态控制接近Mott过渡
Alexey Y Ganin1, Yasuhiro Takabayashi, Peter Jeglic
1Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.
Nature
|May 21, 2010
概括
富勒的晶体结构显著影响其电子特性,影响超导和磁性. 不同的C(60)(3-) 离子的包装安排揭示了超导过渡温度和接近Mott金属绝缘体过渡之间的普遍关系.
科学领域:
- 固态物理 固态物理
- 材料科学是一种材料科学.
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 晶体结构决定了固体中的电子特性.
- 高温超导铜氧化物具有有限的结构安排.
- 富勒化物 (A(3) C(60)) 具有超导性和磁性,具有明显的3D打包可能性.
研究的目的:
- 研究C(60)(3-) 离子的空间布局如何控制竞争的超导和磁性基本状态.
- 为了比较面心立方体 (f.c.c.) 的电子特性. 和身体中心立方体 (b.c.c.) 在Cs{3) C{60).
主要方法:
- 隔离和对f.c.c.c.的描述. 是Cs的多态分子 ((3) C ((60).
- 测量超导过渡温度 (T(c)) 和磁性订制温度 (尼尔温度,T(N)).
- 分析晶体结构,电子相关性和莫特金属绝缘体过渡之间的关系.
主要成果:
- f.c.c.c. 的意思 Cs(3) C(60) 在环境压力下是一种磁绝缘体,在压力下变得超导.
- 在f.c.c.c.中进行磁性排序. 与b.c.c.c.相比,Cs (3) C (60) 在一个更低的温度 (T (N) = 2.2 K) 发生. Cs(3) C(60) (T(N) = 46 K. 这样一个
- 在f.c.c.中的超导过渡温度. Cs(3) C(60) 是 35 K,而 b.c.c. Cs(3) C(60) 表示 38 K.
结论:
- 电子活跃单元的空间布局深刻影响了超导和磁性特性.
- 超导过渡温度 (T ((c)) 尺度普遍与Mott金属绝缘体过渡相近,无论晶体包装如何.
- 这项研究突出了电子相关性在超高温超导超富勒里德超导中的重要性.
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