在高压下,在EuPd3S4中强烈增强磁排序温度和结构/价值转换
Shuyuan Huyan1,2, Dominic H Ryan3, Tyler J Slade1,2
1Ames National Laboratory, US DOE, Iowa State University, Ames, IA 50011.
概括
高压增强了EuPd3S4中的反铁磁排序,诱导了结构过渡和从混合Eu2+/Eu3+到完全Eu3+的价值转移. 这揭示了磁力和电子状态的压力驱动的变化.
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
- 高压物理 高压物理
背景情况:
- 欧洲硫化 (EuPd3S4) 是一种不均的混合价值化合物.
- 了解其在压力下的行为对于探索新的电子和磁性特性至关重要.
研究的目的:
- 综合调查高压对EuPd3S4.4的物理性质的影响.
- 阐明结构过渡,磁性排序和价值状态变化之间的关系.
主要方法:
- 电力运输测量测量电力运输测量
- 在X射线衍射 (XRD) 中.
- 时间域151Eu同步子Mössbauer光谱学
- 在X射线吸收光谱学 (XAS) 中.
- 高压技术 (高达 ~ 29 GPa)
主要成果:
- 反铁磁排序温度 (T) 随着压力迅速增加,达到19-29GPa左右的平原.
- 观察到由压力诱导的第一阶结构转变,从立方对称到四角对称.
- 莫斯巴乌尔和XAS光谱学揭示了一个从混合Eu2+/Eu3+到完全Eu3+的价值过渡,大约28GPa,与磁性排序消失相吻合.
- 欧4f状态和导电带之间的增强混合可能驱动T的初始增加.
结论:
- 压力显著增强了EuPd3S4.4.中的反铁磁排序.
- 在高压下,同时发生结构阶段过渡和价值状态向完全三价欧的变化.
- 这些发现凸显了在极端条件下的混合价值化合物中结构,磁性和电子配置之间的复杂相互作用.
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