在铁磁孔道格子CeCo_{2}中增强异常Nernst效应As_{2}
Shuyue Guan1, Weian Guo2, Pengyu Zheng2
1Peking University, International Center for Quantum Materials, School of Physics, Beijing 100871, China.
Physical review letters
|February 6, 2026
概括
研究人员在铁磁Kondo网格CeCo2As2.2中观察到一个增强的异常Nernst效应 (ANE). 这种效应与拓磁体中的贝里曲率有关,归因于f-轨道平面带.
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
- 量子材料是一种量子材料.
背景情况:
- 异常的Nernst效应 (ANE) 是一种热电现象,从磁性材料中的温度梯度产生横向电压.
- ANE受到费米能量附近的贝里曲率 (BC) 的强烈影响,特别是在拓磁体中.
- 孔多格子,像CeCo2As2一样,由于局部f电子和导电电子之间的相互作用,表现出复杂的电子行为.
研究的目的:
- 为了研究铁磁Kondo网格CeCo2As2.2.中的自发异常Nernst效应.
- 探索贝里曲率,平面带和在这个材料中观察到的ANE之间的关系.
- 了解相关性驱动拓在Kondo格子系统中的作用.
主要方法:
- 在CeCo2As2.2.中对异常的Nernst效应和Seebeck系数进行实验测量.
- 理论分析将观察到的ANE与贝里曲率和电子带结构联系起来.
- 关于CeCo2As2.2.的铁磁Kondo格子属性的表征
主要成果:
- 在CeCo2As2中观察到增强的自发异常Nernst效应,超过了Seebeck系数.
- 大量的异常纳斯特系数归因于f-轨道主导的平面带中的强烈贝里曲率.
- 这些发现表明费米能量被固定在一个拓平面带内.
结论:
- CeCo2As2表现出显著的异常Nernst效应,由拓电子状态驱动.
- 这项研究强调了Kondo格子系统中对热电性质的相关性驱动拓学的重要性.
- 这种材料作为探索拓现象和热电应用的有希望的平台.
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