节点超导体CeCoIn_{5}中的正常费米表面通过热导体揭示
Sangyun Lee1, Duk Y Kim1, Priscila F S Rosa1
1<a href="https://ror.org/01e41cf67">Los Alamos National Laboratory</a>, Los Alamos, New Mexico 87545, USA.
Physical review letters
|June 21, 2024
概括
研究人员使用旋转磁场研究了重超导体CeCoIn_{5}. 他们在导热性中发现了尖的共振,证明这些与CeCoIn的独特费米表面结构有关.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 超导性研究 超导性研究
- 量子材料是一种量子材料.
背景情况:
- 像CeCoIn_{5}这样的重超导体具有复杂的电子特性.
- 了解超导和费米表面拓学的相互作用至关重要.
- 之前的研究暗示了CeCoIn_{5}中的场角依赖现象.
研究的目的:
- 研究在旋转磁场下CeCoIn_{5}的导热性中观察到的共振的起源.
- 阐明费米表面结构在超导状态中的作用.
- 探索热导度测量在探测超导材料中的实用性.
主要方法:
- 用旋转磁场测量CeCoIn_{5}中的导热率.
- 在反节点方向沿着应用热电流 (J ឫស ឫស ឫស [100]).
- 与先前使用热流沿节点方向进行的实验进行比较 (J Handikou[110]).
- 密度函数理论 (DFT) 模型计算状态的电子密度.
主要成果:
- 在相对于热流的特定磁场角度 (Θ≈12°) 观察到热导率的尖共振.
- 这种共振在晶体学上与先前报告的共振保持一致,证实其起源于费米表面结构.
- DFT的计算支持了实验结果,显示了与场方向相对应的状态密度的峰值.
结论:
- 在CeCoIn_{5}中观察到的导热共振绝对与其费米表面结构有关.
- 非冷凝的兰道准粒子被认为是这些共振的原因.
- 旋转磁场导热度测量提供了一个强大的工具,用于探测超导体内费米表面的正常区域.
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