DFT study on electronic and optical properties of graphene under an external electric field
Abdelhafid Najim, Omar Bajjou, Mustapha Boulghallat, Khalid Rahmani, Lhouceine Moulaoui
Abstract
The paper investigates the electronic and optical properties of graphene, under the external electric field ( E ext ) according to perpendicular direction, using density functional theory ( DFT ). Applying the E ext to the graphene sheet modifies its electronic and optical properties, including the band gap energy, total density of states ( TDOS ), absorption coefficient, dielectric function, and refractive index. Graphene’s band gap is opened by the application of E ext to its structure. As a result of the effect of E ext on graphene layer, its absorption coefficient increases in the ultraviolet ( UV ) range and decreases in the visible range. We found that the electronic and optical properties of graphene material, can be altered by a perpendicular excitation applied to its structure.