在AgMn7O12中具有明显的电荷,轨道和旋转顺序的坚固晶体相分离
Dabiao Lu1,2, Jie Zhang1,2, Haoting Zhao1,2
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Inorganic chemistry
|January 31, 2024
概括
这项研究合成了银氧化物 (AgMn7O12),在180K时表现出结构相变.由于相隔,这种转变导致电荷排序和显著的磁阻效应.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 具有总式AA'3B4O12的四重矿氧化物具有复杂的电子和磁性.
- 这些材料中的A位点排序可以导致独特的电荷和轨道排序现象.
- 了解结构-属性关系对于设计新型功能材料至关重要.
研究的目的:
- 为了合成和表征AgMn7O12四重矿氧化物.
- 为了研究AgMn7O12.12的结构,电荷和磁性特性.
- 探索该材料中相位分离和磁电阻之间的关系.
主要方法:
- 使用了高压和高温合成方法.
- 使用X射线衍射来确定晶体结构和相位过渡.
- 进行了磁感应度测量,以确定磁排序温度.
- 进行了磁阻测量,以评估材料对磁场的反应.
主要成果:
- 成功合成了AgMn7O12,在室温下结晶成一个立方Im-3对称,具有特定的电荷分布.
- 一个结构阶段过渡到单临床C2/m对称发生在180K左右,导致B位电荷和轨道顺序.
- 电荷/轨道顺序相与初始立方相在广泛的温度范围内共存.
- 在125K和90K附近的有序相中观察到反铁磁过渡,而在35K左右的立方相中出现了短距离的铁磁相关性.
- 由于强大的相隔,在过渡温度以下观察到相当大的磁电阻效应.
结论:
- AgMn7O12显示了结构,电荷,轨道和磁性排序的复杂相互作用.
- 阶段分离是AgMn7O12的一个关键特征,显著影响其物理性质.
- 观察到的磁电阻凸显了这种材料在磁场传感或记忆器件中的应用潜力.
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