在纯铁磁Kondo网格中奇怪的金属行为
Bin Shen1, Yongjun Zhang1, Yashar Komijani2
1Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou, China.
Nature
|March 6, 2020
概括
奇怪的金属,通常与反铁磁性有关,可以在铁磁体中出现. 这项研究揭示了由纠驱动的铁磁量子关键性, 挑战了关于奇怪金属行为的先前假设.
科学领域:
- 凝聚物质物理学
- 量子材料科学
背景情况:
- 量子临界点附近的奇异金属的异常性质仍然是一个.
- 奇怪的金属通常与非传统的超导和反铁磁QCP有关,表明高度纠的量子状态.
- 铁磁体以前被认为是不太可能的宿主,
研究的目的:
- 在压力诱导的QCP中调查铁磁材料中出现奇怪的金属行为.
- 探索量子纠在铁磁量子关键性的作用.
- 挑战一种普遍的观念,即奇异金属与抗铁磁性QCP完全相关.
主要方法:
- 使用特定热量和压力下的电阻测量.
- 在其压力诱导的QCP附近研究了铁磁Kondo格子材料.
- 分析了局部时刻和导电电子之间的纠模式的转换.
主要成果:
- 证明了CeRh$_{6}$Ge$_{4}$中的铁磁过渡可以连续抑制到零温度,诱导奇怪的金属行为.
- 确定强磁异性作为一个关键因素,通过三重共振价值键引入纠.
- 在QCP观察到从三重共振价值键到Kondo纠单体对的纠变化,导致费米表面体积跳跃.
结论:
- 由于量子纠, 铁磁量子关键性可能会产生奇怪的金属行为.
- 强磁性异构在铁磁体中产生纠起着至关重要的作用.
- 量子纠,而不是反铁磁的破坏,被认为是奇怪金属现象的常见驱动因素.
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