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Updated: Jun 8, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Excitonic effects in the optical conductivity of gated graphene
N M R Peres1, R M Ribeiro, A H Castro Neto
1Department of Physics and Center of Physics, University of Minho, P-4710-057, Braga, Portugal.
Abstract:
We study the effect of electron-electron interactions in the optical conductivity of graphene under an applied gate and derive a generalization of Elliott's formula, commonly used for semiconductors, for the optical intensity. We show that excitonic resonances are responsible for several features of the experimentally measured midinfrared response of graphene such as the increase of the conductivity beyond the universal value above the Fermi blocked regime, the broadening of the absorption at the threshold, and the decrease of the optical conductivity at higher frequencies.
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