Abstract
Surface metallization of Si(001) has been observed at high temperatures, but its explanation is controversial. Such a temperature-induced metallization can be explained in terms of a symmetric-dimer model where symmetric dimers are alternately displaced up and down along the dimer rows. We find that this symmetric-dimer model has an electronlike Fermi surface around the point and a hole pocket centered at the point, in good agreement with angle-resolved photoemission spectroscopy data. Since the symmetric-dimer structure is more favored over the conventional symmetric-dimer structure, its presence may be confirmed by a more detailed analysis of recent reflection high-energy electron-diffraction data which showed the phase transition from a buckled- to a symmetric-dimer structure at high temperatures.
- Received 20 September 2004
DOI:https://doi.org/10.1103/PhysRevB.71.075307
©2005 American Physical Society