前体 skyrmion 状态接近于奇拉磁体的温度排序
Andrey O Leonov1,2,3
1International Institute for Sustainability with Knotted Chiral Meta Matter, Kagamiyama, Higashi Hiroshima, Hiroshima 739-8511, Japan.
Physical chemistry chemical physics : PCCP
|October 18, 2023
概括
奇拉尔Dzyaloshinskii-Moriya相互作用稳定了磁铁中的 skyrmion 格子. 这些格子表现出复杂的阶段和过渡,形成由异构和拓性质稳定的转移稳定状态.
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
- 磁力学 磁力学 是一种
背景情况:
- 奇拉磁体表现出Dzyaloshinskii-Moriya相互作用 (DMI),使得 skyrmion形成成为可能.
- Skyrmions是拓保护的旋转纹理,在数据存储和旋转电子学中具有潜在的应用.
- 多个skyrmionic状态及其相关的磁性相对于理解部分秩序和A相等现象至关重要.
研究的目的:
- 使用现象学Dzyaloshinskii模型,以数值获得 skyrmion格子 (SkL) 的精确解决方案.
- 阐明控制这些斯基尔米翁格子形成和稳定的物理机制.
- 研究不同磁场下 skyrmion 纹理的行为及其相位过渡.
主要方法:
- 基于标准现象学Dzyaloshinskii模型的数值模拟.
- 对 skyrmion 格子属性的分析,包括六角形和正方形分层格子.
- 在增强的磁场下对相位过渡的研究.
主要成果:
- 确定了±π-skyrmions的六角格子和π/2-skyrmions的正方形分层格子作为绑定的 skyrmion状态.
- 证明了这些 skyrmion 格子在热力学上只有在订制温度附近才稳定.
- 观察到不同纹理之间的相位过渡,最终在磁化矩阵中形成孤立的 skyrmion-filaments.
结论:
- 在现象学模型中,Skyrmion格子是元稳定的状态,形螺旋是平衡状态.
- 异位和拓性质可以稳定 skyrmionic 纹理,而不是简单的螺旋.
- 斯基米昂凝聚物的拓性质导致了依赖于历史的和歇斯底里的磁化过程在奇拉磁体中.
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