Atomic structure of the single step and dynamics of Sn adatoms on the Si(111)-\sqrt{3}\times\sqrt{3}-Sn surface

Abstract

The atomic structure of well-ordered single steps on the Si(111)-\sqrt{3}\times\sqrt{3}-Sn surface and the dynamics of Sn adatoms in the vicinity of these steps was studied. The work was performed using low-temperature scanning tunneling microscopy (STM) and ab initio calculations based on the density-functional theory. The STM tip was used to record the tunneling current versus time on top of oscillating adatoms, keeping the feedback loop turned off. The dynamics of adatoms, detected as the telegraph noise present in the tunneling current, was registered near the steps at 80 K. The atomic structure model of the single steps consisting of Sn atomic chains along the steps was developed. This structure leads to the formation of potential double wells near the steps acting as traps for Sn atoms and explains the fluctuating current recorded in these areas.

arXiv comment9 pages, 8 figures

References in corpus (5)

• The SIESTA method for ab initio order-N materials simulation
• Efficient index handling of multidimensional periodic boundary conditions
• Triangular Mott-Hubbard Insulator Phases of Sn/Si(111) and Sn/Ge(111) Surfaces
• Realistic modeling of the electronic structure and the effect of correlations for Sn/Si(111) and Sn/Ge(111) surfaces
• Stability and structure of atomic chains on Si(111)

Cited by in corpus (1)

• Crucial role of vibrational entropy in the Si(111)-7$\times$7 surface structure stability