在Megabar压力下观察到添加化中可能发生的超导转变
Xingbin Zhao1, Yu Huang1, Shuailing Ma1
1Institute of High Pressure Physics, School of Physical Scientific and Technology, Ningbo University, Ningbo, 315211, People's Republic of China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|November 27, 2024
概括
研究人员在化物合的化中探索了超导性,这是一种声称是室温超导体的材料. 然而,这项研究在更低的温度 (6.5K和2.1K) 下在高压下观察到超导,而不是在近环境条件下.
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
- 高压物理 高压物理
背景情况:
- 寻求室温超导是物理学的一个主要目标.
- 最近关于添加化化 (LuH$_{2\pm x}$N$_y$) 中近环境超导性的说法,由于不可重现性,面临着显著的怀疑.
研究的目的:
- 为了研究在高压下合成的化化的超导特性.
- 为了澄清关于这种物质系统中超导性的相互矛盾的报告.
主要方法:
- 使用高压和高温技术合成LuH_{2\pm x}$N$_y$样本.
- 在现场进行X射线衍射以表征结构相位过渡.
- 温度依赖的电阻和磁场依赖的电阻测量.
主要成果:
- 在59GPa时观察到高压相变为Fm-3m-LuH$_{3\pm x}$N$_y$.
- 在95GPa时检测到两个超导过渡,临界温度 (T$_c$) 约为6.5K和2.1K.
- 在Fm-3m阶段,高临界场 (μ$_0$H$_{c2}$(0) 在163 GPa时被测量为3.3 T.
结论:
- 合成的LuH$_{2\pm x}$N$_y$在高压下在低温 (低于6.5K) 上表现出超导性.
- 结果表明,以前报告的近环境超导性说法在研究条件下可能无法重现.
- 这项工作为了解复杂的相位图和添加剂化的超导行为提供了至关重要的数据.
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