基本素质的磁性属性的定量理论
Leonid V Pourovskii1,2, Alena Vishina3, Olle Eriksson3,4
1CPHT, CNRS, École polytechnique, Institut Polytechnique de Paris, Paris, France.
概括
元素 (Pr) 由于其单晶晶场基本状态而非磁性. 先进的ab-initio计算证实了这一点,解释了Pr金属及其表面缺乏磁性.
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
- 量子力学就是量子力学.
背景情况:
- 元素 (Pr) 是一种稀土元素,以其独特的缺乏有序磁性而闻名.
- 实验发现表明,Pr 4f ^ 2 配置中的单晶晶场 (CF) 基态对这种非磁性行为负责.
研究的目的:
- 从理论上确定dhcp Pr.的晶场潜力和基本状态属性.
- 在没有磁性的情况下,研究网站间交换相互作用的作用.
- 为了探索 Pr (0001) 表面的磁性特性.
主要方法:
- 结合密度函数理论 (DFT) 与动态平均场理论 (DMFT) 在Hubbard-I近似中.
- 为dhcp Pr. Pr. 构建了一个有效的磁性哈密尔顿数.
- 使用磁力定理计算了网站间交换相互作用.
主要成果:
- 在dhcp Pr. Pr. 中对两个不等价的 Pr 站点预测的单点晶场地面状态.
- 证明了网站间的交换相互作用不足以克服晶体场与磁场双重之间的差距.
- 发现单子基态在 Pr (0001) 表面持续存在,但与激发单子的能量差距减少.
结论:
- Ab-initio理论成功地解释了元素 Pr. 的非磁性状态.
- 单片基态的强度防止了传统的磁性排序,即使在表面.
- 表面的能量差距减少表明了新的二维多极秩序的潜力.
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