在偏向交换的铁磁-反铁磁双层中,零场磁性 skyrmions
M Pankratova1,2, O Eriksson1,2, A Bergman1
1Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala, Sweden.
概括
在铁磁-抗铁磁双层中,铁磁 skyrmions 在没有外部场的情况下得到稳定. 接口效应和材料特性是控制斯基米翁行为和稳定性的关键.
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
- 计算物理 计算物理
背景情况:
- 铁磁 skyrmions 是具有数据存储潜力的拓保护的旋转纹理.
- 稳定 skyrmions 通常需要外部磁场,限制实际应用.
- 交换偏差系统为控制接口上的磁现象提供了一条路线.
研究的目的:
- 在没有外部磁场的铁磁-抗铁磁 (FM-AFM) 双层中研究铁磁 skyrmions 的稳定性.
- 探索接口补偿,温度和材料参数对 skyrmion 稳定性的影响.
- 了解接口粗在 skyrmion 形成中的作用.
主要方法:
- 用原子自旋动力学模拟来建模FM-AFM双层.
- 模拟被认为是补偿,未补偿和部分未补偿的接口.
- 分析了温度的影响,平面间交换,Dzyaloshinskii-Moriya相互作用和磁性异构性.
主要成果:
- 由于AFM的有效场,在FM层中稳定了个别的 skyrmion 和 skyrmion 格子,特别是在未补偿的接口.
- 在补偿的FM-AFM接口中,Skyrmions也得到了稳定.
- 发现接口粗性在补偿和未补偿系统中稳定了 skyrmions,扩大了适用的交换相互作用的范围.
结论:
- 铁磁 skyrmions 可以在零外部磁场使用交换偏差的FM-AFM双层稳定.
- 接口属性,包括补偿和粗度,对于skyrmion的稳定和控制至关重要.
- 这项工作为基于skyrmion的技术设计材料提供了一条途径,而不需要外部场.
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