在多铁体候选物GdCrO3中确定多个相的磁性结构
Pascal Manuel1, Dmitry Khalyavin1, Fabio Orlandi1
1ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Didcot OX11 0QX, Oxfordshire UK.
概括
研究人员研究了加多氧化物 (GdCrO3) 的多铁应用. 中子衍射证实了三个磁相,揭示了对于理解潜在的内存设备功能至关重要的复杂结构.
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
- 晶体学 晶体学是指结晶学.
背景情况:
- 对于低功耗和多状态内存设备而言,多铁材料具有显著的兴趣.
- 基于矿的化合物,如GdCrO3,因其潜在的多铁性质而被探索.
- 以前的研究表明GdCrO3的铁电行为,但受到泄漏和不清楚的歇斯底里循环的限制.
研究的目的:
- 确定新的多铁化合物,特别是对基于矿的GdCrO3.3进行研究.
- 通过中子衍射来确定GdCrO3的磁性结构.
- 为了将观察到的磁相与物理性质相关联,并了解其复杂结构背后的机制.
主要方法:
- 在一个同位素160GdCrO3样本上进行了中子衍射实验,在WISH衍射仪上,ISIS.
- 测量包括电容和PE歇斯底里循环,以探测铁电行为.
- 使用最新的报告准则进行磁性结构分析.
主要成果:
- 铁电行为被增强电容所暗示,但被显著的泄漏和缺乏清晰的P-E环所阻碍.
- 检测到极相低于2K,可能与加多 (Gd) 排序有关.
- 中子衍射证实了三个连续的磁相 (相称,旋转重定位,不相称) 是温度的函数,与磁化数据一致.
结论:
- 这项研究证实了GdCrO3复杂的磁性结构,其特点是有三个不同的温度依赖的磁性相.
- 确定的磁结构为讨论物理性质和理解对观察到的复杂性负责的合提供了基础.
- 对驱动这些复杂结构的机制进行进一步的研究是有必要的,因为它可能在先进的电子设备中得到应用.
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