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تسجيل مستخدم جديدEffects due to backscattering and pseudogap features in graphene nanoribbons with single vacancies
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We present a systematic study of electron backscattering phenomena during conduction for graphene nanoribbons with single-vacancy scatterers and dimensions within the capabilities of modern lithographic techniques. Our analysis builds upon an textit{ab initio} parameterized semiempirical model that breaks electron-hole symmetry and nonequilibrium Greens function methods for the calculation of the conductance distribution $g$. The underlying mechanism is based on wavefunction localizations and perturbations that in the case of the first $pi-pi{}^*$ plateau can give rise to impurity-like pseudogaps with both donor and acceptor characteristics. Confinement and geometry are crucial for the manifestation of such effects. Self-consistent quantum transport calculations characterize vacancies as local charging centers that can induce electrostatic inhomogeneities on the ribbon topology.
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