Eur. Phys. J. B (2012) 85: 222
https://doi.org/10.1140/epjb/e2012-30119-x

Regular Article

Impurity effects in graphene

Department of Physics, Faculty of Sciences, Ankara University, 06100 Tandoğan, Ankara, Turkey

^a e-mail: altanhan@science.ankara.edu.tr

Received: 9 February 2012
Received in final form: 25 April 2012
Published online: 27 June 2012

Abstract

We study the effects of impurities on the electronic properties of graphene. The tight-binding Hamiltonian with impurities has been diagonalized by a series of canonical transformations to obtain energy dispersions. Impurity effects on energy is observed as a band gap opening in donor type impurities, whereas acceptor type impurities do not create a gap. However the linear dispersions near the Dirac point turn to quadratic form for both types of impurities. Density of states are also calculated analytically.