Berlin 2005 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
O: Oberflächenphysik
O 39: Nanostrukturen IV
O 39.4: Vortrag
Dienstag, 8. März 2005, 11:30–11:45, TU EB420
Local electronic properties of the one-dimensional Si(557)-Au surface — •M. Sauter1, M. Schöck2, R. Hoffmann1, C. Sürgers1, and H. v. Löhneysen1,3 — 1Physikalisches Institut and DFG Center for Functional Nanostructures (CFN), Universität Karlsruhe, D-76128 Karlsruhe, Germany — 2Institut for Fysik og Astronomi, Aarhus Universitet, DK-8000 Århus, Denmark — 3Forschungszentrum Karlsruhe, Institut für Festkörperphysik, D-76021 Karlsruhe, Germany
The local electronic properties of the Si(557)-Au surface, obtained by deposition of 0.2 monolayers Au on vicinal Si(111) and subsequent annealing, are investigated by scanning tunneling microscopy (STM) and spectroscopy at different temperatures. Images taken at room temperature show the characteristic surface structure of chains adjacent to diffuse stripes. At T = 77 K the images show a voltage dependent contrast which disagrees with the previously reported interpretation in terms of a Peierls-like transition occurring below 260 K [1]. The voltage-dependent contrast is is confirmed by atomically-resolved tunneling spectra which indicate metallic or semiconductor-like behavior depending on the type of protrusion. The results are discussed by comparison with a recent calculation of the electronic surface-band structure of Si(557)-Au [2].
[1] J. R. Ahn et al., Phys. Rev. Lett. 91, 196403 (2003)
[2] D. Sánchez-Portal et al., Phys. Rev. Lett. 93, 146803 (2004)