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L. Linhart, J. Burgdörfer, F. Libisch:
"Accurate modeling of defects in graphene transport calculations";
Physical Review B, 97 (2018), 035430.

We present an approach for embedding defect structures modeled by density functional theory into large-scale tight-binding simulations. We extract local tight-binding parameters for the vicinity of the defect site using Wannier functions. In the transition region between the bulk lattice and the defect the tight-binding parameters are continuously adjusted to approach the bulk limit far away from the defect. This embedding approach allows for an accurate high-level treatment of the defect orbitals using as many as ten nearest neighbors while keeping a small number of nearest neighbors in the bulk to render the overall computational cost reasonable. As an example of our approach, we consider an extended graphene lattice decorated with Stone-Wales defects, flower defects, double vacancies, or silicon substitutes. We predict distinct scattering patterns mirroring the defect symmetries and magnitude that should be experimentally accessible.

graphene, defects, quantum transport

http://dx.doi.org/10.1103/PhysRevB.97.035430

https://publik.tuwien.ac.at/files/publik_277868.pdf