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.
- Publication:
-
Journal of Physics Condensed Matter
- Pub Date:
- July 2013
- DOI:
- 10.1088/0953-8984/25/26/262001
- Bibcode:
- 2013JPCM...25z2001A