Influence of interlayer coupling and intra-layer Coulomb interaction on electronic transport in bilayer graphene

• Analysis of electronic transport in bilayer graphene.
• The expressions are obtained using Kubo formula of conductivity.
• Perpendicular conductivity increases with interlayer coupling.
• Coulomb energy suppresses the rate of increase of σ⊥/σ⊥0 with temperature.

Calculations of renormalized perpendicular conductivity within Kubo formula employing single particle temperature dependent Green's function formalism for bilayer graphene has been attempted. On the basis of numerical analysis, perpendicular conductivity as a function of temperature, interlayer coupling, onsite Coulomb interaction and carrier concentration per site has been analyzed for both AA- and AB-stacked bilayer graphene. It is found that perpendicular conductivity increases with interlayer coupling and also with temperature at low temperatures while at higher temperatures, there is saturation in perpendicular conductivity. Influences of onsite Coulomb interaction and carrier concentration per site on perpendicular conductivity is just opposite to each other while onsite Coulomb energy suppresses the rate of increase of σ⊥/σ⊥0 with temperature, on the other hand increase in carrier density per site enhance this rate significantly. Finally, theoretically obtained results on temperature dependent perpendicular conductivity are viewed in terms of electronic transport data as well as recent theoretical works available in bilayer graphene.

Temperature dependence of the perpendicular conductivity at different values of the onsite Coulomb interaction energy (U = 8 eV, 9 eV and 10 eV) in AA-stacked bilayer graphene.Figure optionsDownload as PowerPoint slide