Transport length scales in disordered graphene-based materials: strong localization regimes and dimensionality effects.
We report on a numerical study of quantum transport in disordered two dimensional graphene and graphene nanoribbons. By using the Kubo and the Landauer approaches, transport length scales in the diffusive (mean free path and charge mobilities) and localized regimes (localization lengths) are computed, assuming a short range disorder (Anderson-type). The electronic systems are found to undergo a conventional Anderson localization in the zero-temperature limit, in agreement with localization scaling theory. Localization lengths in weakly disordered ribbons are found to strongly fluctuate depending on their edge symmetry, but always remain several orders of magnitude smaller than those computed for 2D graphene for the same disorder strength. This pinpoints the role of transport dimensionality and edge effects.
Lherbier
Aurélien
A
Laboratoire des Technologies de la Microélectronique, Unité Mixte de Recherche 5129/Centre National de la Recherche Scientifique, CEA, 17 rue des Martyrs, Grenoble, France.
Biel
Blanca
B
Niquet
Yann-Michel
YM
Roche
Stephan
S