Theoretical modeling of experimental HREEL spectra for supported graphene

• Published in: Physics letters. A 2014-06, Vol.378 (30-31), p.2206-2210
• Main Authors: Radović, Ivan, Borka, Duško, Mišković, Zoran L.
• Format: Article
• Language: English
• Subjects: Approximation; Computational fluid dynamics; Dielectric function; Excitation spectra; Frequency ranges; Graphene; HREELS; Mathematical analysis; Solid state physics; Spectra
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2014.06.001

We present a simple model for the resonant feature designated as the π plasmon in single-layer graphene supported by a metal substrate, which is excited via high-resolution electron energy loss spectroscopy (HREELS) in the off-specular scattering geometry. Using a two-dimensional, two-fluid hydrodynamic model for interband transitions of graphene's π and σ electrons and an empirical Drude–Lorentz model for the metal in the local approximation enables us to reproduce, at the qualitative and semi-quantitative levels, the typical experimental features of the HREEL spectra in the visible to the ultraviolet frequency range. •We present an analytical model for the HREELS of graphene/metal system.•We use the 2D, two-fluid hydrodynamic model for graphene's π and σ electrons.•We use a simple dielectric function of the Drude–Lorentz type for a metal substrate.•HREEL spectra are well reproduced qualitatively and semi-quantitatively.