在一个二维铁磁磁体中,单轴磁晶异型的异国气温依赖在一个二维铁磁体中
Jiawei Liu1, Jiawei Jiang1,2, Liming Wang2
1Nanjing University, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and Jiangsu Provincial Key Laboratory for Nanotechnology, Nanjing 210093, China.
Physical review letters
|April 7, 2025
概括
我们在2D铁磁磁体的单轴磁晶异性 (UMA) 中发现了异国情调的温度依赖性. 在20K以下,UMA下降,但在20K以上,它意外地增加,为数据存储技术提供了洞察力.
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
- 量子材料是一种量子材料.
背景情况:
- 单轴磁晶异构 (UMA) 对于数据存储和量子应用至关重要.
- 了解UMA在2D铁磁体中的温度依赖性是很重要的,因为受限电子和晶格动态.
研究的目的:
- 为了研究UMA在2D范德瓦尔斯铁磁体中的温度依赖性.
- 探索不同温度下Fe3GeTe2中UMA的异常行为.
主要方法:
- 取决于温度的X射线衍射测量.
- 第一原则计算.第一原则计算.
- 对UMA常数K_{u1}(T) 的温度依赖性的分析.
主要成果:
- Fe3GeTe2 呈现出前所未有的UMA的异常温度依赖.
- 在20K以下,K_{u1}(T) 遵循正规的下降趋势 (Akulov-Zener-Callen-Callen类型).
- 在20K以上,K_{u1}(T) 显示出异常的增长趋势 (卡尔型),原因是铁磁交换合的增强和格子动态的改变.
结论:
- 格子变化和增强的铁磁交换合在高温下保持了两离子异性质.
- 改变的流动性和网格热膨胀触发了异国情调的K_{u1}(T) 行为.
- 这些发现加深了对UMA温度依赖性的理解,并有助于优化热辅助磁记录技术.
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