Deshpande A, Yildirim H, Kara A, Acharya D P, Vaughn J, Rahman T S, Hla S-W
Physics and Astronomy Department, Ohio University, Athens, Ohio 45701, USA.
Phys Rev Lett. 2007 Jan 12;98(2):028304. doi: 10.1103/PhysRevLett.98.028304. Epub 2007 Jan 11.
We investigate the atomistic details of a single atom-extraction process realized by using the scanning tunneling microscope tip-cluster interaction on a Ag(111) surface at 6 K. Single atoms are extracted from a silver cluster one atom at a time using small tunneling biases less than 35 mV. Combined total energy calculations and molecular dynamics simulations show a lowering of the atom-extraction barrier upon approaching the tip to the cluster. Thus, a mere tuning of the proximity between the tip and the cluster governs the extraction process. The atomic precision and reproducibility of this procedure are demonstrated by repeatedly extracting single atoms from a silver cluster on an atom-by-atom basis.
我们研究了在6K温度下，利用扫描隧道显微镜针尖与银（111）表面上的团簇相互作用实现的单原子提取过程的原子细节。使用小于35mV的小隧道偏压，从银团簇中一次提取一个单原子。结合总能量计算和分子动力学模拟表明，当针尖靠近团簇时，原子提取势垒降低。因此，仅仅调整针尖与团簇之间的距离就能控制提取过程。通过逐个原子地从银团簇中反复提取单原子，证明了该过程的原子精度和可重复性。
