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arXiv · 0904.4400

Linear Response and the Thomas-Fermi Approximation in Undoped Graphene

L. Brey·H. A. Fertig
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Abstract

We analyze the range of validity of Thomas Fermi theory for describing charge density modulations induced by external potentials in neutral graphene. We compare exact results obtained from a tight-binding calculation with those of linear response theory and the Thomas Fermi approximation. For experimentally interesting ranges of size and density amplitudes (electron densities less than $\sim 10 ^{11} cm ^{-2}$, and spatial length scales below $\sim 20 nm$), linear response is significantly more accurate than Thomas Fermi theory.

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L. Brey, H. A. Fertig. 2009-04-28. Linear Response and the Thomas-Fermi Approximation in Undoped Graphene. https://doi.org/10.1103/physrevb.80.035406

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