铁磁Cu6和Cu18集群在BaCuO2+x中的反铁磁排序和偏磁行为
Science (New York, N.Y.)
|April 15, 1994
概括
磁化和中子衍射揭示了BaCuO2+x的磁性行为. 铜6环集群显示反铁磁排序,而铜18球体集群仍然具有磁性,量子效应最小.
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
- 磁力学 磁力学 是一种
背景情况:
- 氧化铜 (BaCuO2+x) 是一种复杂的氧化物,在磁力学中具有潜在的应用.
- 了解其组成集群的磁性质对于材料设计至关重要.
研究的目的:
- 通过磁化和中子衍射来研究BaCuO2+x的磁性行为.
- 描述Cu(6) 环和Cu(18) 球团的磁顺序.
主要方法:
- 多晶 BaCuO2+x 样品经过磁化测量.
- 中子衍射被用来探测磁体结构和秩序.
主要成果:
- ((6) 环集群表现出铁磁性基态,其旋转很大,并且在15K以下以反铁磁性方式排序.
- (18) 球状星团具有铁磁基态,但直到2K仍然具有重磁性.
- 在Cu6环中,有序的矩是每Cu的0.89(5) 波尔磁子,这表明量子波动效应很小.
结论:
- BaCuO2+x显示出由其独特的集群结构驱动的磁性行为组合.
- 6) 环表现出强大的反铁磁排序,而 (18) 球在低温下排序较差.
- 预测模型建议铁磁交集群顺序为1K以下的Cu(18) 集群.
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