New structure model for the GaAs(001)-c(4x4) surface.
The surface structure of the As-stabilized GaAs(001)-c(4 x 4) surface has been studied. We show that the seemingly established three As-dimer model is incompatible with experimental data and propose here a new structure model which has three Ga-As dimers per c(4 x 4) unit cell. This mixed dimer model, confirmed by the rocking-curve analysis of reflection high-energy electron diffraction and first-principles calculations, resolves disagreements in the interpretation of several previous experiments. A good agreement between the observed scanning tunneling microscopy image and the simulated one further confirms the newly proposed model.
Ohtake
Akihiro
A
National Institute for Materials Science (NIMS), Tsukuba 305-0047, Japan.
Nakamura
Jun
J
Tsukamoto
Shiro
S
Koguchi
Nobuyuki
N
Natori
Akiko
A