| AVS 55th International Symposium & Exhibition | |
| Surface Science | Wednesday Sessions |
| Session SS1+NC-WeM |
| Session: | Surface Structure and Morphology |
| Presenter: | N. Zaki, Columbia University |
| Authors: | N. Zaki, Columbia University D.V. Potapenko, Columbia University R.M. Osgood, Columbia University P.D. Johnson, Brookhaven National Laboratory |
| Correspondent: | Click to Email |
Due to stronger electron-electron interactions, 1-D systems are predicted and, in some cases, have been shown to exhibit unique and exotic electronic physical properties, such as spin-charge separation, spin-splitting in a nonmagnetic metal,1,2 and fractional-charge phase solitons.3 One route to the formation of 1-D systems is by self-assembly using low-index vicinal crystal surfaces. In this regard, we have successfully formed 1-atom wide Co wires using Cu(775), a 7-atom wide stepped array with (111) terraces. Contrary to a recently reported DFT prediction, the Co wires are not laterally encapsulated but are positioned exactly at the step edge. Furthermore, the wires can be relatively long; in one case, a wire measured 160 Co atoms. We will present STM studies of this system performed at room temperature and under UHV. While vicinal Cu(111) does exhibit “frizz” at the steps when scanning above cryogenic temperatures, the Co wires pin the edges, visually accentuating their presence under STM. Furthermore, we observe a lower density of states for the Co wires as compared with the Cu steps, which also serves to differentiate the two metals. Cu(111) possess a surface projected bandgap which may electronically decouple the wire electrons that reside in this gap. Correspondingly, STS measurements of these atom-wide wires will be discussed.
1D. Sanchez-Portal, S. Riikonen, and R. M. Martin, PRL 93, 146803 (2004)
2I. Barke, Fan Zheng, T. K. Rugheimer, and F. J. Himpsel, PRL 97 226405 (2006)
3P.C. Snijders, S. Rogge, and H. H. Weitering, PRL 96, 076801 (2006) .