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arXiv · 1211.6606

Analytical and numerical study of uncorrelated disorder on a honeycomb lattice

Abstract

We consider a tight-binding model on the regular honeycomb lattice with uncorrelated on-site disorder. We use two independent methods (recursive Green's function and self-consistent Born approximation) to extract the scattering mean free path, the scattering mean free time, the density of states and the localization length as a function of the disorder strength. The two methods give excellent quantitative agreement for these single-particle properties. Furthermore, a finite-size scaling analysis reveals that all localization lengths for different lattice sizes and different energies (including the energy at the Dirac points) collapse onto a single curve, in agreement with the one-parameter scaling theory of localization. The predictions of the self-consistent theory of localization however fail to quantitatively reproduce these numerically-extracted localization lengths.

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Kean Loon Lee, Benoît Grémaud, Christian Miniatura, Dominique Delande. 2012-11-28. Analytical and numerical study of uncorrelated disorder on a honeycomb lattice. https://doi.org/10.1103/physrevb.87.144202

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