螺旋液态与前体铁磁集群在挫败的玻璃四边形螺旋 Zn 中反铁磁相互作用
S K Jena1, M S Seehra2, T Sarkar3
1Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
概括
这项研究揭示了四边形旋转子Zn0.8Cu0.2FeMnO4表现出复杂的磁性,包括短距离秩序和集群旋转玻璃状态,但缺乏远距离磁性秩序. 这些发现揭示了丧的旋转系统中的异国情调的磁性行为.
科学领域:
- 材料科学 材料科学 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:
- 具有八面体位的磁离子的脊柱化合物 (AB2O4) 经常表现出磁丧,阻碍远程秩序 (LRO) 并促进异国情调的磁性状态.
- 雅恩-泰勒活性Mn3+离子诱导旋转的四角性,影响它们的磁性和结构性质.
研究的目的:
- 为了研究四角旋转 Zn0.8Cu0.2FeMnO4.4 的磁性特性.
- 了解短距离顺序 (SRO),集群旋转玻璃 (SG) 行为,以及该材料中没有LRO之间的相互作用.
主要方法:
- 用X射线衍射 (XRD) 和X射线光电子光谱 (XPS) 进行组合分析.
- 取决于温度的磁化 (M),ac/dc磁感应 (χ', χ'', χ),热容量 (Cp) 和中子衍射 (ND) 的测量.
- 分析M与H,hysteresis循环和热残磁化 (MTRM(t)) 以探测磁性排序和动态.
主要成果:
- 组成被确定为 (Zn0.82+Cu0.22+) A[Fe0.42+Fe0.63+Mn3+]BO4‒δ.
- 在没有LRO的情况下观察到复杂的SRO,在高温 (θ ≈ 185 K) 时具有主导的铁磁 (FM) 合.
- 发现了大约在46.6K以下的集群自旋玻璃 (SG) 状态和在9K以下的自旋液体 (SL) 行为的证据,热容量没有峰值表明LRO.
结论:
- Zn0.8Cu0.2FeMnO4表现出反铁磁相互作用的FM集群,导致集群SG状态和随后的SL行为,但没有LRO.
- 磁性属性受到特定的离子状态 (高旋转Cu2+,Fe2+;低旋转Mn3+,Fe3+) 和四角扭曲的影响.
- 这项研究突出了挫败的旋的复杂磁相图和非传统磁态的出现.
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