在高压下合成的LaT ((M) BN和La3T ((M2) B2N3 (T ((M) =过渡金属) 中的超导性
Naoki Imamura1, Hiroshi Mizoguchi, Hideo Hosono
1Frontier Research Center, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
Journal of the American Chemical Society
|January 28, 2012
概括
新的层状化物表现出大量超导性,临界温度高达6.7K. 这些材料具有独特的电子结构,由过渡金属-相互作用产生的,影响其超导和磁性特性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 无机化学 无机化学
背景情况:
- 层状尼化物是一种有趣的材料类,在电子和超导领域具有潜在的应用.
- 了解晶体结构,电子状态和物理特性之间的关系对于设计新型材料至关重要.
研究的目的:
- 通过一般式 (LaN) (n) (T) (M2) (B) (2)) 来合成和表征新的层状尼化物.
- 研究电子结构及其与超导和磁性质的相关性.
- 探索这些材料在超导性方面的潜力.
主要方法:
- 使用高压合成技术来制备分层的onitrides.
- 进行密度函数理论 (DFT) 计算,分析 (BN) 单元和 LaN 层的电子状态.
- 对于合成的化合物,测量了超导过渡温度 (T(c)).
主要成果:
- 已经成功合成了几种层状化物,包括LaNiBN,CaNiBN和LaPtBN.
- 在LaNiBN (T(c) ≈4.1K,CaNiBN (T(c) ≈2.2K和LaPtBN (T(c) ≈6.7K中观察到散装超导性.
- 据DFT的计算显示,费米水平位于T{M}{d}-B{2p}抗结带中,主要的T{M}{d}带位于E{F}以下.
- 非超导性化合物表现出保利磁性行为,这是由于来自强共价键的漫游电子.
结论:
- 合成的层状尼化物显示出有前途的超导性能.
- 电子结构,特别是T{M}{d}-B{2p}相互作用,在确定超导和磁性行为方面发挥着关键作用.
- 这些发现为进一步研究基于分层化结构的高温超导体开辟了道路.
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