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arXiv · 0705.3040

Electron waves in chemically substituted graphene

N. M. R. Peres·F. D. Klironomos·S. -W. Tsai·J. R. Santos·J. M. B. Lopes dos Santos·A. H. Castro Neto
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Abstract

We present exact analytical and numerical results for the electronic spectra and the Friedel oscillations around a substitutional impurity atom in a graphene lattice. A chemical dopant in graphene introduces changes in the on-site potential as well as in the hopping amplitude. We employ a T-matrix formalism and find that disorder in the hopping introduces additional interference terms around the impurity that can be understood in terms of bound, semi-bound, and unbound processes for the Dirac electrons. These interference effects can be detected by scanning tunneling microscopy.

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N. M. R. Peres, F. D. Klironomos, S. -W. Tsai, J. R. Santos, J. M. B. Lopes dos Santos, A. H. Castro Neto. 2007-05-21. Electron waves in chemically substituted graphene. https://doi.org/10.1209/0295-5075/80/67007

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