无尽的迪拉克节点线和高移动性在Kagome半金属Ni3In2Se2:一个理论和实验研究
Sanand Kumar Pradhan1, Sharadnarayan Pradhan1, Priyanath Mal2
1Department of Pure and Applied Physics, Guru Ghasidas Vishwavidyalaya, Koni, Bilaspur 495009, C. G., India.
概括
这项研究揭示了Ni3In2Se2是一种kagome拓半金属,具有独特的电子特性. 它的带结构和运输行为表明了先进量子材料应用的潜力.
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:
- 卡戈梅晶格晶体在量子材料研究中是必不可少的,因为它们具有独特的传输特性.
- 这些特性源于复杂的带结构,包括节点线和环.
研究的目的:
- 为了研究Ni3In2Se2 kagome拓半金属的电子传输特性.
- 执行第一原理计算,以了解其带结构和拓性质.
主要方法:
- 带结构的第一原则计算,带有和没有旋转轨道合 (SOC).
- 计算Z2指数以确定拓性质.
- 对温度依赖的电阻和磁阻 (MR) 的分析.
- 霍尔效应测量适用于一个两带模型.
主要成果:
- Ni3In2Se2 呈现出半金属性质,三条带穿过费米水平.
- 一个小带间隙 (10 meV) 与SOC打开,Z2指数证实了非碎的拓.
- 在没有SOC的情况下观察到六条迪拉克节点线和两个带有pi-Berry阶段的节点环.
- 电阻是由50K以下的s-d带间散射和50K以上的电子声波散射控制的.
- 在2K和9T时的最大MR为120%,具有很高的载体流动性 (~3000cm^2V^-1s^-1).
- 该材料具有电子孔补偿,从而提高载体移动性和MR.
- 量子干扰效应表明由于节点线费米离子扩散导致的二维弱反局部化.
结论:
- Ni3In2Se2是一种电子孔补偿的kagome拓半金属,具有强大的拓性质.
- 它独特的电子结构和传输现象,包括高MR和弱反局部化,使其成为量子材料的有希望的候选者.
- 观察到的散射机制和载体动态为复杂的拓材料中的电子行为提供了洞察力.
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