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arXiv · 0711.1018

Average Density of States in Disordered Graphene systems

Shangduan Wu·Lei Jing·Qunxiang Li·Q. W. Shi·Jie Chen·Xiaoping Wang·Jinlong Yang
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Abstract

In this paper, the average density of states (ADOS) with a binary alloy disorder in disordered graphene systems are calculated based on the recursion method. We observe an obvious resonant peak caused by interactions with surrounding impurities and an anti-resonance dip in ADOS curves near the Dirac point. We also find that the resonance energy (Er) and the dip position are sensitive to the concentration of disorders (x) and their on-site potentials (v). An linear relation, not only holds when the impurity concentration is low but this relation can be further extended to high impurity concentration regime with certain constraints. We also calculate the ADOS with a finite density of vacancies and compare our results with the previous theoretical results.

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Shangduan Wu, Lei Jing, Qunxiang Li, Q. W. Shi, Jie Chen, Xiaoping Wang, Jinlong Yang. 2007-11-07. Average Density of States in Disordered Graphene systems. https://doi.org/10.1103/physrevb.77.195411

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