The resistance of dual-gated bilayer graphene is measured as a function of temperature and gating electric fields in the Corbino geometry which precludes edge transport. The temperature-dependent resistance is quantitatively described by a two channel conductance model including parallel thermal activation and variable range hopping channels, which gives the electric-field-dependent band gap whose magnitude is found to be in good agreement with infrared absorption experiments. Low temperature transport is similar to previous studies of dual-gated bilayer graphene with edges, suggesting that edge transport does not play an important role.
@article{arxiv.1010.1036,
title = {Charge transport in dual gated bilayer graphene with Corbino geometry},
author = {Jun Yan and Michael S. Fuhrer},
journal= {arXiv preprint arXiv:1010.1036},
year = {2010}
}