Collective modes of doped graphene and a standard 2DEG in a strong magnetic field: linear magneto-plasmons versus magneto-excitons

Abstract

A doped graphene layer in the integer quantum Hall regime reveals a highly unusual particle-hole excitation spectrum, which is calculated from the dynamical polarizability in the random phase approximation. We find that the elementary neutral excitations in graphene in a magnetic field are unlike those of a standard two-dimensional electron gas (2DEG): in addition to the upper-hybrid mode, the particle-hole spectrum is reorganized in linear magneto-plasmons that disperse roughly parallel to $\omega =v_{F}q$, instead of the usual horizontal (almost dispersionless) magneto-excitons. These modes could be detected in an inelastic light scattering experiment.

8 pages, 3 figures. Version accepted for publication in Phys. Rev. B

References in corpus (6)

• The electronic properties of graphene
• Dielectric function, screening, and plasmons in 2D graphene
• The Role of Electron-electron Interactions in Graphene ARPES Spectra
• Excitations from Filled Landau Levels in Graphene
• The quasiparticle spectral function in doped graphene
• Inter-band magnetoplasmons in mono- and bi-layer graphene