在 NdMn2Ge2中调查 skyrmion 稳定性和核心极性逆转
Samuel K Treves1,2,3, Victor Ukleev3,4, Andreas Apseros2,3
1Department of Physics, University of Basel, 4056, Basel, Switzerland.
Scientific reports
|January 3, 2025
概括
这项研究揭示了稀土铁磁体中稳定的,室温的斯基米安气泡,可以通过磁场控制. 这些纳米级旋转纹理显示了未来旋转电子设备的潜力.
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
- 纳米技术纳米技术
背景情况:
- 斯基尔米尼旋转纹理是纳米级的磁性结构,具有数据存储的潜力.
- 了解它们在新材料中的稳定性和控制性对于旋转电子学至关重要.
研究的目的:
- 为了研究稀土复杂非线性铁磁体中 skyrmion 气泡的形成和特性.
- 为了评估这些 skyrmions 在不同的条件下的稳定性和可控性.
主要方法:
- 用X射线显微镜观察斯基米翁格子.
- 空 (NV) 纳米级磁成像用于流浪场映射.
- 微磁模拟用于模拟磁性行为.
主要成果:
- 经过场冷却后,在没有磁场的情况下在室温下观察到转移稳定的 skyrmion 气泡.
- 在室温高达330K的情况下,Skyrmions表现出强性.
- 通过磁场强度和方向来控制Skyrmion的行为.
- 在样本表面附近测量了几mT的流浪场.
- 发现Dzyaloshinskii-Moriya相互作用对于观察到的行为是不必要的,并且其包含改变了核心极性.
结论:
- 稀土铁磁体在室温下拥有稳定,强大的 skyrmion 气泡.
- 这些 skyrmions 可使用外部磁场控制.
- 这些发现支持了这些 skyrmions 对于 spintronic 应用的潜力.
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