Interband -like plasmon in silicene grown on silver
arXiv:1708.03858 · doi:10.1103/PhysRevB.97.041401
Abstract
Silicene, the two-dimensional allotrope of silicon, is predicted to exist in a low-buckled honeycomb lattice, characterized by semimetallic electronic bands with graphenelike energy-momentum dispersions around the Fermi level (represented by touching Dirac cones). Single layers of silicene are mostly synthesized by depositing silicon on top of silver, where, however, the different phases observed to date are so strongly hybridized with the substrate that not only the Dirac cones, but also the whole valence and conduction states of ideal silicene appear to be lost. Here, we provide evidence that at least part of this semimetallic behavior is preserved by the coexistence of more silicene phases, epitaxially grown on Ag(111). In particular, we combine electron energy loss spectroscopy and time-dependent density functional theory to characterize the low-energy plasmon of a multiphase-silicene/Ag(111) sample, prepared at controlled silicon coverage and growth temperature. We find that this mode survives the interaction with the substrate, being perfectly matched with the π-like plasmon of ideal silicene. We therefore suggest that the weakened interaction of multiphase silicene with the substrate may provide a unique platform with the potential to develop different applications based on two-dimensional silicon systems.
arXiv comment12 pages, 14 figures (including the supplemental material)
References in corpus (27)
- Electric Field Effect in Atomically Thin Carbon Films
- Two and one-dimensional honeycomb structures of silicon and germanium
- Quantum Spin Hall Effect in Silicene
- Epitaxial Growth of a Silicene Sheet
- Evidence of silicene in honeycomb structures of silicon on Ag(111)
- Electrically Tunable Band Gap in Silicene
- Electronic structure of silicon-based nanostructures
- Evidence for Dirac Fermions in a honeycomb lattice based on silicon
- Valley-Polarized Quantum Anomalous-Hall Effects in Silicene
- Growth of silicene layers on Ag(111): unexpected effect of the substrate temperature
- Linear plasmon dispersion in single-wall carbon nanotubes and the collective excitation spectrum of graphene
- Does Silicene on Ag(111) Have a Dirac Cone?
- Silicene Structures on Silver Surfaces
- Silicene on Ag(111): an honeycomb lattice without Dirac bands
- Dynamical Polarization Function, Plasmons and Screening in Silicene and Other Buckled Honeycomb Lattices
- Coexistence of multiple silicene phases in silicon grown on Ag(111)
- Direct Evidence of Interaction-Induced Dirac Cones in Monolayer Silicene/Ag(111) System
- Absence of Dirac Electrons in Silicene on Ag (111) Surfaces
- Combined AFM and STM measurements of a silicene sheet grown on Ag(111) surface
- Introduction to the Physics of Silicene and other 2D Materials
- Plasmon modes of graphene nanoribbons with periodic planar arrangements
- Acoustic plasmons in extrinsic free-standing graphene
- Probing the Topological Phase Transition via Density Oscillations in Silicene and Germanene
- Compelling experimental evidence of a Dirac cone in the electronic structure of a 2D Silicon layer
- EELS study of the epitaxial graphene/Ni(111) and graphene/Au/Ni(111) systems
- Plasmon properties and hybridization effects in Silicene
- Exploring semiconductor substrates for Silicene epitaxy