Density dependent exchange contribution to ∂μ/∂ n in extrinsic graphene

Original · EN

We calculate ∂μ/∂ n in extrinsic graphene as a function of carrier density n at zero temperature by obtaining the electronic self-energy within the Hartree-Fock approximation. The exchange-driven Dirac-point logarithmic singularity in the quasiparticle velocity of intrinsic graphene disappears in the extrinsic case. The calculated renormalized ∂μ/∂ n in extrinsic graphene has the same qualitative n-12 density dependence as the inverse bare density of states with a 20% enhancement from the corresponding bare value, a relatively weak effect compared to the corresponding parabolic-band case.