title: Impurities in a biased graphene bilayer.
abstract: We study the problem of impurities and midgap states in a biased graphene bilayer. We show that the properties of the bound states, such as localization lengths and binding energies, can be controlled externally by an electric field effect. Moreover, the band gap is renormalized and impurity bands are created at finite impurity concentrations. Using the coherent potential approximation, we calculate the electronic density of states and its dependence on the applied bias voltage.
authors.affiliation: Department of Physics, Boston University, Boston, Massachusetts 02215, USA.
authors.forename: Johan
authors.initials: J
authors.lastname: Nilsson
authors.forename: A H
authors.initials: AH
authors.lastname: Castro Neto