可调节的铁磁旋转在化纳米管中进行排序,具有拓性吸附的
1Institute of Nano Science, Nanjing University of Aeronautics and Astronautics, No. 29 of Yudao Street, Nanjing 210016, People's Republic of China.
Journal of the American Chemical Society
|May 1, 2009
概括
在化纳米管上的原子会产生远程铁磁自旋排序. 这种效果可以通过管半径来调整,从而使其在自旋电子设备中具有潜在的应用.
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:
- 化纳米管 (BNNTs) 是电子应用的有希望的材料.
- 控制纳米材料的磁性对自旋电子学至关重要.
研究的目的:
- 为了研究吸附化化纳米管的磁性特性.
- 探索纳米管半径对自旋排序的影响.
- 在F-BNNTs中开发可调节的压磁性质.
主要方法:
- 使用第一原则计算,在BNNTs上建模吸附.
- 分析了纳米管半径和磁性特性之间的关系.
- 曲率调制用于控制铁磁排序.
主要成果:
- 原子的拓吸附会在BNNT中诱导远程铁磁自旋排序.
- 旋转极化和磁矩随着纳米管半径的减少而增加.
- 半金属性在直径为3.3 Å时得到,与平板不同.
- 半径依赖的行为允许增强或灭铁磁排序.
结论:
- 吸附的BNNT表现出可调节的铁磁性质,取决于管半径.
- 这种取决于半径的行为使得可以开发压磁纳米管.
- 这些发现为设计可调节的自旋电子设备提供了新的途径.
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