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Density dependent exchange contribution to $\partialμ/\partial n$ in extrinsic graphene

E. H. Hwang·Ben Yu-Kuang Hu·S. Das Sarma
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Abstract

We calculate $\partialμ/\partial n$ 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 $\partialμ/\partial n$ in extrinsic graphene has the same qualitative $n^{-\frac12}$ 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.

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E. H. Hwang, Ben Yu-Kuang Hu, S. Das Sarma. 2007-12-03. Density dependent exchange contribution to $\partialμ/\partial n$ in extrinsic graphene. https://doi.org/10.1103/physrevlett.99.226801

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