Electric transport of double gated bilayer graphene devices is studied as a function of charge density and bandgap. A top gate electrode can be used to control locally the Fermi level to create a pn junction between the double-gated and single-gated region. These bilayer graphene pn diodes are characterized by non-linear currents and directional current rectification, and we show the rectified direction of the source-drain voltage can be controlled by using gate voltages. A systematic study of the pn junction characteristics allows to extract a gate-dependent bandgap value which ranges from 0 meV to 130 meV.
@article{arxiv.1201.1105,
title = {Gate tunable non-linear currents in bilayer graphene diodes},
author = {Hiroki Shioya and Michihisa Yamamoto and Saverio Russo and Monica F. Craciun and Seigo Tarucha},
journal= {arXiv preprint arXiv:1201.1105},
year = {2012}
}