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arXiv · 1201.1105

Gate tunable non-linear currents in bilayer graphene diodes

Hiroki Shioya·Michihisa Yamamoto·Saverio Russo·Monica F. Craciun·Seigo Tarucha
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Abstract

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.

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Hiroki Shioya, Michihisa Yamamoto, Saverio Russo, Monica F. Craciun, Seigo Tarucha. 2012-01-05. Gate tunable non-linear currents in bilayer graphene diodes. https://doi.org/10.1063/1.3676441

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