在横向原子操纵中控制单个原子的动力学
Joseph A Stroscio1, Robert J Celotta
1Electron Physics Group, National Institute of Standards and Technology, Gaithersburg, MD 20899-8412, USA. joseph.stroscio@nist.gov
概括
我们观察到一个单一的原子在铜的表面位置之间切换. 尖端高度和电压影响了原子运动,揭示了对原子操纵和表面动态的洞察力.
科学领域:
- 表面科学是一门科学.
- 原子操纵是一种原子操纵.
- 扫描道显微镜的扫描方法
背景情况:
- 了解表面上的原子动力学对于纳米级工程至关重要.
- 低温扫描道显微镜 (LT-STM) 能够在原子层面进行表面研究.
研究的目的:
- 在铜 (111) 表面进行横向操纵时研究单个 (Co) 原子的动力学.
- 为了揭示Co结合点的位置和在扫描尖的捕获潜力中的原子运动.
主要方法:
- 使用低温扫描道显微镜 (LT-STM) 进行原子操纵.
- 分析了随机电报噪声,以确定六角密集 (hcp) 和面中心立方 (fcc) 位点之间的过渡.
- 改变探头高度和道电压,以研究它们对原子动态的影响.
主要成果:
- 详细的成像揭示了在尖端的捕获潜力内的原子运动.
- 观察到随机的电报噪声,表明hcp和fcc站点之间的Co Atom切换.
- 证明尖端高度改变了表面潜力,影响了停留时间.
- 在低 (<5 meV) 和高道电压下确定了不同的行为,后者显示电压的依赖性,表明振动加热.
结论:
- 这项研究阐明了单个Co原子在Cu{111) 表面上的动态行为.
- 用STM尖端进行侧向操纵可以诱导位点切换,受表面电位和尖端参数的影响.
- 通过不弹性电子散射进行振动加热,在更高的道电压下起作用,影响原子转移速率.
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