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arXiv · 1211.7170

Ab-initio transport fingerprints for resonant scattering in graphene

Karri Saloriutta·Andreas Uppstu·Ari Harju·Martti J. Puska
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Abstract

We have recently shown that by using a scaling approach for randomly distributed topological defects in graphene, reliable estimates for transmission properties of macroscopic samples can be calculated based even on single-defect calculations [A. Uppstu et al., Phys. Rev. B 85, 041401 (2012)]. We now extend this approach of energy-dependent scattering cross sections to the case of adsorbates on graphene by studying hydrogen and carbon adatoms as well as epoxide and hydroxyl groups. We show that a qualitative understanding of resonant scattering can be gained through density functional theory results for a single-defect system, providing a transmission "fingerprint" characterizing each adsorbate type. This information can be used to reliably predict the elastic mean free path for moderate defect densities directly using ab-initio methods. We present tight-binding parameters for carbon and epoxide adsorbates, obtained to match the density-functional theory based scattering cross sections.

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Karri Saloriutta, Andreas Uppstu, Ari Harju, Martti J. Puska. 2012-11-30. Ab-initio transport fingerprints for resonant scattering in graphene. https://doi.org/10.1103/physrevb.86.235417

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