title: Presence of gapped silicene-derived band in the prototypical (3 × 3) silicene phase on silver (111) surfaces.
abstract: By mapping the low-energy electronic dynamics using angle resolved photoemission spectroscopy (ARPES), we have shed light on essential electronic characteristics of the (3 × 3) silicene phase on Ag(111) surfaces. In particular, our results show a silicene-derived band with a clear gap and linear energy-momentum dispersion near the Fermi level at the Γ symmetry point of the (3 × 3) phase at several distinctive Brillouin zones. Moreover, we have confirmed that the large buckling of ~0.7 Å of this silicene structure induces the opening of a gap close to the Fermi level higher than at least 0.3 eV, in agreement with recent reported photoemission results. The two-dimensional character of the charge carriers has also been revealed by the photon energy invariance of the gapped silicene band, suggesting a limited silicene-silver hybridization, in disagreement with recent density-functional theory (DFT) predictions.
authors.affiliation: Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin-BP 48, F-91192 Gif sur Yvette Cedex, France.
authors.forename: J
authors.initials: J
authors.lastname: Avila
authors.forename: P
authors.initials: P
authors.lastname: De Padova
authors.forename: S
authors.initials: S
authors.lastname: Cho
authors.forename: I
authors.initials: I
authors.lastname: Colambo
authors.forename: S
authors.initials: S
authors.lastname: Lorcy
authors.forename: C
authors.initials: C
authors.lastname: Quaresima
authors.forename: P
authors.initials: P
authors.lastname: Vogt
authors.forename: A
authors.initials: A
authors.lastname: Resta
authors.forename: G
authors.initials: G
authors.lastname: Le Lay
authors.forename: M C
authors.initials: MC
authors.lastname: Asensio
mesh_terms: D003080:Cold Temperature; D008956:Models, Chemical; D056951:Photoelectron Spectroscopy; D012825:Silicon / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012834:Silver; D012825:Silicon