在热磁FeP中拓驱动的线性磁阻
D J Campbell1,2, J Collini1,3, J Sławińska4,5
1Maryland Quantum Materials Center, Department of Physics, University of Maryland, College Park, MD, USA.
概括
铁化物 (FeP) 呈现出强大的线性电磁阻,当磁场沿其c轴应用时. 这种行为与其电子带结构中的一个独特的半迪拉克点有关.
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
- 固态物理 固态物理
背景情况:
- 铁化物 (FeP) 属于二进制pnictides的MnP型结构家族.
- 这些材料具有非对称的晶体对称性,在元素变化中保持带结构特征.
- FeP与CRA和MnP具有磁性顺序的相似之处,CRA和MnP具有压力诱导的超导性.
研究的目的:
- 研究FeP单晶体的高磁场行为.
- 描述磁阻及其电场依赖性的特征.
- 探索电子带结构和观察到的现象之间的关系.
主要方法:
- 在高质量的FeP单晶体上进行高磁场实验.
- 电阻测量最高可达35特斯拉.
- 量子振荡频率分析.
- 与电子结构计算进行比较.
主要成果:
- 阻力在35 T时增加了其零场值的几百倍.
- 异常线性电场对电阻的依赖性观察到与沿c轴的电场.
- 量子振荡与带结构中的半迪拉克点联系在一起.
- 磁电阻的振幅和线性来自不同的机制.
结论:
- 在FeP中的线性磁阻强烈依赖于磁场的方向.
- 确定了一个半迪拉克点,一个对称性保护的带结构特征.
- 有序的磁力和拓波段结构有助于观察到的线性磁阻.
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