在绝缘范德瓦尔斯铁磁体中的拓线纹理
Sergey Grebenchuk1,2, Conor McKeever3, Magdalena Grzeszczyk1
1Institute for Functional Intelligent Materials, National University of Singapore, Singapore, 117544, Singapore.
Advanced materials (Deerfield Beach, Fla.)
|February 2, 2024
概括
研究人员探索了用于自旋电子的磁绝缘体,发现CrBr3范德瓦尔斯 (vdW) 铁磁体可以产生多种拓自旋纹理. 这些纹理,包括 skyrmions,可以通过厚度,磁场和光来控制.
科学领域:
- 这就是Spintronics.
- 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
背景情况:
- 在信息存储等先进的自旋电子应用中,拓式自旋纹理至关重要.
- 磁绝缘器为节能的自旋电子器件提供低阻尼和减少散射.
- 控制磁性材料中的旋转纹理是一个关键的挑战.
研究的目的:
- 为了研究在绝缘CrBr3范德瓦尔斯 (vdW) 铁磁体中产生和控制拓旋转纹理.
- 在不同的条件下探索各种旋转纹理的共存和相互转换.
- 了解样本厚度,磁场和光学刺激在纹理操纵中的作用.
主要方法:
- 高分辨率磁力显微镜 (MFM) 用于图像旋转纹理.
- 大规模的微磁模拟来模拟磁性行为.
- 洛伦兹传输电子显微镜 (LTEM) 分析磁性力.
- 光发光 (PL) 光谱与循环偏振探测激子-子合.
主要成果:
- 在CrBr3 vdW铁磁体中证明了条纹域, skyrmion晶体和磁域的共存.
- 确定了一种相切换机制,用于在不同的旋转纹理之间进行内在选择和转换.
- 通过厚度工程可控制的混合性 (布洛赫型,尼尔型,混合型).
- 通过光学探测器观察到激子-子合.
结论:
- CrBr3 vdW铁磁铁提供了一个多功能平台,用于生成和操纵各种拓旋转纹理.
- 厚度,磁场和光学控制使得可以调整磁纹性和磁纹类型.
- 这些发现突出了VDW磁绝缘器作为创建有序 skyrmion 格子用于设备集成的有希望的.
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