Search

We perform a scanning tunneling microscopy and spectroscopy study on the electronic structures of √3 × √3-silicene on Ag(111). It is found that the coupling strength of √3 × √3-silicene with the Ag(111) substrate is variable in different regions, giving rise to notable effects in experiments. This evidence of decoupling or variable interaction of silicene with the substrate is helpful to in-depth understanding of the structure and electronic properties of silicene. [ABSTRACT FROM AUTHOR]

It is known that, when Ag is deposited on Si(111)-7×7 substrates in a conventional growth procedure at room temperature, no atomically flat Ag film could be obtained. We use scanning tunneling microscopy and low-energy electron diffraction to investigate the growth of ultra-thin Ag films on the Si(111) substrates at room temperature. Our study reveals that, upon introducing a Si(111)-√3 × √3-Ga buffer layer, atomically flat Ag films can easily grow on Si(111) with a critical thickness of two monolayers. Moreover, Ag film growth follows a layer-by-layer mode with further deposition. This novel growth behavior of Ag can be explained in terms of a free electron model (i.e., particle in a box) and kinetic Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

The electronic structure of silicene on Ag(111) is studied by scanning tunneling microscopy and angle resolved photoemission spectroscopy. A flat band at 0.9 eV below the Fermi level is revealed. We find that the flat band is strongly suppressed near atomic defects, domain boundaries and step edges compared to that on the flat terraces. The discovery of the flat band and its sensitivity to local perturbations provides a new way to manipulate the electronic structure and properties of silicene. [ABSTRACT FROM AUTHOR]