Ag/Si(111)root 3 x root 3: Surface band splitting and the inequivalent triangle model

作者：Zhang H M^*; Uhrberg R I G

来源：Physical Review B, 2006, 74(19): 195329.

DOI：10.1103/PhysRevB.74.195329

The atomic and electronic structures of the Ag/Si(111)root 3x root 3 surface are currently under debate. By employing angle-resolved valence-band spectroscopy, the surface band dispersions around the (K) over bar point of the Ag/Si(111)root 3x root 3 surface have been investigated in detail. Contrary to a recent study, we conclude that the S-2 and S-3 surface state bands do not show any detectable split at 100 K. Thus, photoemission spectra at both room temperature and 100 K show only a single peak at the (K) over bar point without any direct evidence of a split. Calculated band structures for the inequivalent triangle (IET) model show a gap at the (K) over bar point in contrast to the honeycomb-chain-trimer (HCT) model. We find, however, that there is no real contradiction between our photoemission data and the IET model provided the energy gap of the latter model is small as indicated by a recent calculation [Phys. Rev. B 70, 245431 (2004)].

• 出版日期2006-11