We study the influence of kinks on the structure of a narrow SB terrace on Si(001) surface by using Monte Carlo simulations (MCS) based on the asymmetric dimer model. Coupling constants among the buckling of the dimers given by the first-principles calculation are used. The SA and SB step edges are treated by the free boundary condition for the buckling of the dimers. The kink at the SA step was treated as an external field to the neighbouring dimer on the SB terrace on the basis of the STM observation results. The fluctuation of the system is suppressed at the dimer row connected to the kink. We find that the system practically corresponds to the one-dimensional Ising spin system with defect spins at low temperature. The influence of the kink appears in a different way in STM images in accordance with the different scales of the observation time. We predict thermal equilibrium behaviour of the narrow SB terrace with kinks at very low temperature.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry