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arXiv · 1106.2940

Screening in graphene antidot lattices

M. H. Schultz·A. P. Jauho·T. G. Pedersen
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Abstract

We compute the dynamical polarization function for a graphene antidot lattice in the random-phase approximation. The computed polarization functions display a much more complicated structure than what is found for pristine graphene (even when evaluated beyond the Dirac-cone approximation); this reflects the miniband structure and the associated van Hove singularities of the antidot lattice. The polarization functions depend on the azimuthal angle of the {\bf q}-vector. We develop approximations to ease the numerical work, and critically evaluate the performance of the various schemes. We also compute the plasmon dispersion law, and find an approximate square-root dependence with a suppressed plasmon frequency as compared to doped graphene. The plasmon dispersion is nearly isotropic, and the developed approximation schemes agree well with the full calculation.

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M. H. Schultz, A. P. Jauho, T. G. Pedersen. 2011-06-15. Screening in graphene antidot lattices. https://doi.org/10.1103/physrevb.84.045428

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