AVS 51st International Symposium
    Surface Science Monday Sessions
       Session SS1-MoM

Paper SS1-MoM1
Electronic Stablization of Nanophase Separation Along Si Atomic Chains

Monday, November 15, 2004, 8:20 am, Room 210B

Session: Electronic Structure and Excitations
Presenter: J.L. McChesney, University of Wisconsin
Authors: J.L. McChesney, University of Wisconsin
J.N. Crain, NIST
V. Perez-Dieste, University of Wisconsin
F. Zheng, University of Wisconsin
M.C. Gallagher, Lakehead University, Canada
F.J. Himpsel, University of Wisconsin
Correspondent: Click to Email
One-dimensional surface structures have received a great deal of interest both for probing the fundamental physics phenomena of low-dimensions and for applications in nano-electronics. The Si(111)5x2-Au surface exhibits one-dimensional tracks with extra Si atoms on top, which have been used to demonstrate an atomic scale memory [1] and to probe the limits of storage density by studying the effects of inter-atomic coupling [2]. Atomic-interactions play a vital role in the determination of the electronic structure and vice versa. In an effort to elucidate this connection we used angle-resolved photoemission spectroscopy to probe the relevant electronic states in the vicinity of the Fermi level EF [3]. They are located at the zone boundaries of a 5x4 unit cell which explains the 5x4 periodicity of the inter-atomic potential [2]. This corresponds to the preferred spacing of the Si adatoms while the optimum chain doping would correspond to a 5x8 arrangement of the Si adatoms [4]. We propose that the nanoscale phase separation of this surface [5] into semiconducting 5x4 and metallic 5x2 sections is a way to accommodate these conflicting requirements. 1. R. Bennnewitz et.al., Nanotech. 13, 499 (2002). 2. A. Kirakosian et.al., Phys. Rev. B. 67, 205412 (2003). 3. J. L. McChesney et.al., submitted to Phys. Rev. B. 4. S. C. Erwin, Phys. Rev. Lett. 91, 206101 (2003). 5. H. S. Yoon et.al., Phys. Rev. Lett 92,096801 (2004). @FootnoteText@ .