Charge accumulation at the boundaries of a graphene strip induced by a gate voltage: Electrostatic approach

The distribution of charge induced by a gate voltage in a graphene strip is investigated. We analytically calculate the charge profile and demonstrate a strong (macroscopic) charge accumulation along the boundaries of a micrometer-wide strip. This charge inhomogeneity is especially important in the quantum Hall regime, where we predict the doubling of the number of edge states and the coexistence of two different types of such states. Applications to graphene-based nanoelectronics are discussed.