在两个f轨道中的超磁性过渡 康多晶格模型模型
Christopher Thomas1, Sébastien Burdin2, Claudine Lacroix3
1Instituto de Física, UFRGS, 91501-970 Porto Alegre, Brazil.
概括
这项研究在横向磁场下探索了一个双轨道的Kondo网格模型. 铁磁性和康多效应在低电场上共存,随着电场的增加,观察到的超磁性过渡.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子多体系统是一个量子多体系统.
- 材料科学 材料科学 材料科学
背景情况:
- 康多格子模型描述了局部 f 电子和导电电子之间的相互作用.
- 系统经常表现出混合的f电子的局部化和脱局部化.
- 磁场显著影响磁性材料中的电子特性.
研究的目的:
- 研究铁磁和康多效应在两个轨道f电子系统中的相互作用.
- 分析横向磁场对这个模型的影响.
- 在Kondo合的存在下描述磁性过渡.
主要方法:
- 一个Kondo格子模型的理论研究与两个f-轨道.
- 包括Hund的合和网站间交换相互作用.
- 分析局部化 (轨道1) 和非局部化 (轨道2) f电子行为.
- 检查系统在低温下对横向磁场的反应 (T→0).
主要成果:
- 铁磁和康多效应的共存在小型横向磁场中被发现.
- 随着横向场的增加和Kondo合的消失,出现了两个不同的超磁性过渡场景.
- 这些转换发生在完全极化状态之前或同时发生,或者在旋转与场对齐后.
结论:
- 该模型为理解f电子系统中复杂的磁性行为提供了一个框架.
- 横向磁场可以诱导丰富的相位过渡,包括超磁性.
- 铁磁和康多效应的共存是低磁场的一个关键特征.
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