在碳酸硫中室温超导
Elliot Snider1, Nathan Dasenbrock-Gammon2, Raymond McBride1
1Department of Mechanical Engineering, School of Engineering and Applied Sciences, University of Rochester, Rochester, NY, USA.
Nature
|October 15, 2020
概括
研究人员在一种新的碳硫化物系统中实现了室温超导. 这一突破为开发低压超导体提供了潜力.
科学领域:
- 凝聚物质物理学
- 材料科学
- 高压物理
背景情况:
- 在实验物理中观察室温超导仍然是一个重大挑战.
- 最近的进展涉及极端压力下的富含的材料的高温超导.
- 硫化 (H2S) 在203K和155GPa时转化为H3S的超导性标志着一个关键发现.
研究的目的:
- 探索碳酸硫系统实现超导的潜力.
- 研究将甲引入超导材料中的富含的前体的效果.
- 在高压下合成和描述一种新型超导材料.
主要方法:
- 元素前体的光化学转化为碳酸硫.
- 使用钻石细胞 (高达275GPa) 施加高压.
- 通过测量零电阻,磁感应和对外部磁场 (高达9 T) 的反应来描述超导性.
- 拉曼光谱被用来探测金属化之前的化学和结构变化.
主要成果:
- 在碳酸硫系统中观察到超导性,其最大过渡温度为287.7 ± 1.2 K (约15°C),在267 ± 10 GPa.
- 超导状态持续在广泛的压力范围内 (140275 GPa),显著增加在220 GPa以上.
- 超导的证据包括零电阻,二磁信号和外部磁场抑制过渡温度.
- 估计的高临界磁场约为62 T,使用金兹堡-兰多模型来确定.
结论:
- 这项研究证明了一种新型的光化学合成碳酸硫的室温超导性.
- 这种三元系统中的化学调节为在压力降低下实现超导提供了一个有希望的途径.
- 这些富含的材料的进一步研究可能为高温超导体的实际应用铺平道路.
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