Evidence for hybrid surface metallic band in (4x4) silicene on Ag(111)

The electronic band structure of monolayer (4 x 4) silicene on Ag(111) is imaged by angle resolved photoelectron spectroscopy. A dominant hybrid surface metallic band is observed to be located near the bulk Ag sp-band which is also faintly visible. The two-dimensional character of the hybrid band has been distinguished against the bulk character of the Ag(111) sp-band by means of photon energy dependence experiments. The surface band exhibits a steep linear dispersion around the (K) over bar Ag point and has a saddle point near the (M) over bar Ag point of Ag(111) resembling the pi-band dispersion in graphene. (C) 2013 AIP Publishing LLC.