在现实空间观测一个二维的 skyrmion 晶体
1Advanced Electron Microscopy Group and High Voltage Electron Microscopy Station, National Institute for Materials Science, Tsukuba 305-0044, Japan. yu.xiuzhen@nims.go.jp
Nature
|June 19, 2010
概括
研究人员用Fe{0.5}Co{0.5}Si薄膜成像了一个二维的 skyrmion 格子,一个旋转的旋转纹理,在Fe{0.5}Co{0.5}Si薄膜. 这种稳定的磁结构,使用洛伦兹传输电子显微镜观察,可以使新的自旋电子现象.
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:
- 晶体秩序超越了原子排列,延伸到像维格纳晶体和磁性秩序这样的电子系统.
- 磁性秩序涉及平行 (铁磁体) 或反平行 (反铁磁体) 旋转对齐.
- 旋转纹理,如拓稳定的 skyrmions,代表复杂的旋转安排,有可能出现新的现象.
研究的目的:
- 在薄膜中图像和描述一个二维的 skyrmion 格子.
- 为了研究观察到的 skyrmion 晶体的稳定性和相位图.
- 探索控制纳米尺度旋转拓的潜力,用于旋转电子应用.
主要方法:
- 现实空间成像使用洛伦兹传输电子显微镜 (LTEM).
- 将正常的磁场 (50-70 mT) 应用于薄膜.
- 实验相位图与蒙特卡洛模拟的比较.
主要成果:
- 在Fe{0.5}Co{0.5}Si薄膜中直接成像六边形的 skyrmions 排列.
- 观测一个稳定的二维 skyrmion 格子,其格子间距为 90 nm.
- 实验相位图显示与模拟很好的一致,并表明在广泛范围内的稳定性,包括接近零度的温度.
结论:
- 一个稳定的,二维的 skyrmion 晶体已经在薄膜上成功成像.
- 观察到的 skyrmion 格子表现出适于受控操纵的特性.
- 这种控制的纳米尺度旋转拓为实现非传统的磁转运效应提供了潜力.
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