基于Pt的超导体LaPt5As的发现
Masaya Fujioka1, Manabu Ishimaru2, Taizo Shibuya3
1Research Institute for Electronic Science, Hokkaido University , Sapporo, Hokkaido 001-0020, Japan.
Journal of the American Chemical Society
|July 28, 2016
概括
一种新型的超导体,兰五化 (LaPt5As),被发现具有独特的晶体结构和2.6K的超导性.高压是形成这种材料的关键
科学领域:
- 材料科学
- 凝聚物质物理学
- 固态化学
背景情况:
- 超导是一种在临界温度以下的某些材料中观察到的量子力学现象.
- 新超导材料的发现对于能传输和磁共振成像技术的发展至关重要.
- 高压合成是一种强大的技术,用于稳定在环境条件下无法获得的新材料相.
研究的目的:
- 在高压下合成的新型超导材料.
- 研究新材料的晶体结构,合成压力和超导特性之间的关系.
- 探索高压合成在材料中发现新相的潜力.
主要方法:
- 使用卡瓦伊型装置进行高压合成.
- 晶体结构的特征.
- 超导过渡温度 (Tc) 的测量.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 一个新的超导体LaPt5As被发现,其超导过渡温度 (Tc) 为2.6K.
- LaPt5As具有独特的晶体结构,具有长c晶格参数 (>60 Å) 和类似网络的Pt层.
- 在约10 GPa的烧结压力下获得单相超导LaPt5As.
- DFT计算表明通过Pt层的超导电流,突出了层结构的作用.
结论:
- LaPt5As是一种具有独特层状晶体结构的新型超导体,表明这种结构是其超导性的关键.
- 高压合成有效地产生单相超导LaPt5As,并为发现新的高压相提供了潜力.
- 由于LaPt5As的多层结构,可以进行结构修改,为未来的材料设计打开了道路.
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