通过在反铁磁材料中扭曲Kagome网格来增强异常的霍尔效应
Subhajit Roychowdhury1,2, Kartik Samanta1, Sukriti Singh1
1Department of Topological Quantum Chemistry, Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany.
概括
这项研究揭示了HoAgGe由于其独特的Kagome旋转冰结构而表现出不寻常的异常霍尔导电性 (AHC). 这些发现为拓磁性材料和丧效应提供了新的见解.
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 量子材料是一种量子材料.
背景情况:
- 拓磁性材料将电子波函数拓与磁性顺序结合起来.
- 铁磁维尔半金属通常表现出强大的异常霍尔导电性 (AHC).
- 非线性反铁磁体通常表现出较小的AHC.
研究的目的:
- 调查HoAgGe中的异常霍尔导电性 (AHC),这是一个抗铁磁 (AFM) 卡戈梅旋冰化合物.
- 探索材料结构,磁性秩序及其电子性质之间的关系.
- 了解观察到的AHC和拓霍尔电阻的起源.
主要方法:
- 在六角ZrNiAl型结构中对HoAgGe进行晶体分析.
- 测量霍尔电阻和异常霍尔导电 (AHC) 作为温度和磁场的函数.
- 贝里曲率和散射机制的理论分析.
主要成果:
- 由于其非平面结构,HoAgGe在2.0K时显示出很大的拓霍尔电阻 (~1.6μΩ-cm).
- 在45 K左右观察到异常高的AHC (2,800 Ω-1 cm-1),明显高于其尼尔温度 (TN ~11 K).
- 在TN以下的AHC归因于来自场诱导的韦尔点的贝里曲率,而在TN以上则占主导地位的斜散射.
结论:
- HoAgGe表现出独特的磁传输特性,源于其挫败的AFM Kagome网格.
- 该研究表明,现场诱导的韦尔点有助于该材料中的AHC.
- HoAgGe提供了一个新的平台来研究反铁磁Kagome网格系统中的挫折.
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