在被反向不对称驱动的表面上,奇拉磁顺序
M Bode1, M Heide, K von Bergmann
1Institute of Applied Physics and Microstructure Research Center, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany. mbode@anl.gov
Nature
|May 15, 2007
概括
研究人员观察到的单个原子层中的奇拉磁性秩序. 这种由Dzyaloshinskii-Moriya相互作用驱动的同体旋转结构对于旋转器件至关重要.
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:
- 奇拉性或单手性在生物分子和粒子物理学中被观察到.
- 磁性材料可以由于在反向不对称晶体场中的Dzyaloshinskii-Moriya相互作用而表现出同体旋转结构.
- 低维系统,与散装金属不同,缺乏结构反向对称性,使同体旋转结构成为可能.
研究的目的:
- 观测和描述单个原子层系统中的奇拉磁性秩序.
- 研究Dzyaloshinskii-Moriya相互作用在低维磁性材料中的作用.
- 探索纳米级性磁铁在旋转电子学中的潜在应用.
主要方法:
- 利用自旋极化扫描道显微镜对磁结构进行成像.
- 在 (110) 基板上研究了的单个原子层.
- 运用定量理论来理解观察到的奇拉顺序.
主要成果:
- 在的单个原子层的磁性秩序中观察到一种特定的性.
- 确定了一个旋转螺旋结构,周期约为12nm,由轻微倾斜的旋转产生的.
- 证实Dzyaloshinskii-Moriya相互作用导致左旋转的旋转环形体.
结论:
- 对于缩小尺寸的磁体,Dzyaloshinskii-Moriya相互作用是显著的.
- 状纳米磁铁对于旋转器件很重要,它可以为数据处理提供旋转扭矩效应.
- 这些发现为微波发射,磁化切换和磁电机方面的进步铺平了道路.
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