在LiCu2P2中缺乏超导性
1National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China.
Journal of the American Chemical Society
|January 27, 2011
概括
这项研究研究了LiCu(2) P(2) 的超导性. 可重复的合成和测量没有发现2K以上的超导过渡,表明金属行为和库里-韦斯磁力.
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:
- 之前的报道表明LiCu(2) P(2) 具有超导性,临界温度 (T(c)) 为3.7K.
- 基于铜的pnictides是新兴电子特性感兴趣的领域.
研究的目的:
- 独立验证LiCu中报告的超导性(2) P(2).
- 为了描述合成的LiCu(2) P(2) 样本的电子和磁性.
- 探索石化测量对LiCu(2) P(2) 的特性的影响.
主要方法:
- 合成多晶和单晶LiCu(2) P(2) 的合成.
- 取决于温度的电阻和DC磁化测量从2K到300K.
- 霍尔效应和磁电阻 (MR) 的测量.
- 合成了Li(1-x) Cu(2) P(2),LiCu(2-x) P(2) 和Li(1+x) Cu(2-x) P(2) 的各种固体测量方法.
主要成果:
- 对于任何合成样本,在电阻或DC磁化超过2K时没有观察到超导过渡.
- 电阻测量表明金属的行为.
- 电直流磁化表现出从2K到300K的库里-斯行为.
- 霍尔效应和MR测量表明LiCu(2) P(2) 的单带特征.
结论:
- 之前报道的LiCu(2) P(2) 的超导性无法复制.
- 合成的LiCu(2) P(2) 显示了金属特性和磁性行为,与局部时刻一致.
- 在研究的LiCu(2) P(2) 系统中,静电测量的变化没有诱导超导.
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