平带调和新兴的旅行磁力在 Sr ((Co1-xPdx) 2作为2中
Santanu Pakhira1,2, Yongbin Lee1, Asish K Kundu3,4
1Ames National Laboratory, Iowa State University, Ames, IA 50011.
概括
在Sr(Co,Pd) 2As2量子材料中微小的替代会诱导强大的磁性秩序. 这种平带不稳定性突出了控制材料中的磁性的新途径.
科学领域:
- 量子材料科学 量子材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 磁性和平带 (FB) 不稳定性是量子材料的关键.
- 在费米能量附近调整一个平面带可以在非磁性化合物中诱导磁性秩序.
研究的目的:
- 调查保利偏磁体SrCo2As2.2中磁性秩序的出现情况.
- 探索非磁性 (Pd) 替代 (Co) 在磁性特性上的作用.
主要方法:
- 温度和磁场依赖的磁性和传输测量.
- 零场中子衍射. 零场中子衍射.
- 光谱分析和理论频段结构计算.
主要成果:
- 2%的Pd替代引发了具有80K的过渡温度的抗铁磁顺序.
- 对于低度的Pd,观察到螺旋磁顺序,在较高度时过渡到复杂的铁磁状态.
- 通过Pd替代的电子兴奋剂使平面带更接近费米能量,增强了斯通纳参数并导致了磁性不稳定.
结论:
- 非磁性元素的替代可以诱导强大的磁性排序,证明了平带不稳定性的关键作用.
- 这种现象为在流动电子系统中调整磁场提供了一个独特的途径.
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