Plasmon-plasmon interaction and the role of buffer in epitaxial graphene micro-flakes
arXiv:2302.09007 · doi:10.1103/PhysRevB.108.045308
Abstract
We investigate the origin of the translational symmetry breaking in epitaxially grown single-layer graphene. Despite the surface morphology of homogeneous graphene films influenced by the presence of mutually parallel SiC surface terraces, the far-infrared magneto-plasmon absorption is almost independent of the angle between the probing light polarization and the orientation of terraces. Based on a detailed analysis of the plasmon absorption lineshape and its behavior in the magnetic field, supported by confocal Raman mapping and atomic force microscopy, we explain this discrepancy by spontaneously formed graphene micro flakes. We further support our conclusions using data collected on artificially created graphene nanoribbons: we recognize similar plasmon origin in artificial ribbons and naturally formed grains. An unexpectedly large plasmon resonance redshift was observed in nanoribbons. In a hydrogen-intercalated sample (which does not contain the buffer), this redshift is quantitatively taken into account by a plasmon-plasmon interaction. In non-intercalated samples featuring a buffer layer, this redshift is due to an interplay between the plasmon-plasmon coupling and Coulomb screening by the buffer-induced interface states. This model determines the density of interface states in good agreement with experimentally reported values.
arXiv comment17 pages, 10 figures, 4 tables
References in corpus (24)
- Graphene plasmonics: A platform for strong light-matter interaction
- Dielectric function, screening, and plasmons in 2D graphene
- Manipulating infrared photons using plasmons in transparent graphene superlattices
- Dynamical polarization of graphene at finite doping
- Mid-infrared plasmons in scaled graphene nanostructures
- An Introduction to Graphene Plasmonics
- Intrinsic Terahertz Plasmons and Magnetoplasmons in Large Scale Monolayer Graphene
- Edge and surface plasmons in graphene nanoribbons
- Charge transfer between epitaxial graphene and silicon carbide
- Hybrid Metal-Graphene Plasmons for Tunable Terahertz Technology
- Anomalously strong pinning of the filling factor nu=2 in epitaxial graphene
- Terahertz Nonlinearity in Graphene Plasmons
- Microwave response of a two-dimensional electron stripe
- Graphene, a material for high temperature devices; intrinsic carrier density, carrier drift velocity, and lattice energy
- Strong plasmon reflection at nanometer-size gaps in monolayer graphene on SiC
- Confined Plasmons in Graphene Microstructures: Experiments and Theory
- Magnetoplasmons in quasi-neutral epitaxial graphene nanoribbons
- Effect of residual gas composition on epitaxial graphene growth on SiC
- Impact of graphene quantum capacitance on transport spectroscopy
- Experimental demonstration of graphene plasmons working close to the near-infrared window
- Reflection Phase Shift of One-dimensional Plasmon Polaritons in Carbon Nanotubes
- Coupling of Plasmon Modes in Graphene Microstructures
- Effects of Screening on Propagation of Graphene Surface Plasmons
- Probing the structure and composition of van der Waals heterostructures using the nonlocality of Dirac plasmons in the terahertz regime