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arXiv · 0809.5025

Tunable Graphene System with Two Decoupled Monolayers

H. Schmidt·T. Luedtke·P. Barthold·E. McCann·V. I. Falko·R. J. Haug
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Abstract

The use of two truly two-dimensional gapless semiconductors, monolayer and bilayer graphene, as current-carrying components in field-effect transistors (FET) gives access to new types of nanoelectronic devices. Here, we report on the development of graphene-based FETs containing two decoupled graphene monolayers manufactured from a single one folded during the exfoliation process. The transport characteristics of these newly-developed devices differ markedly from those manufactured from a single-crystal bilayer. By analyzing Shubnikov-de Haas oscillations, we demonstrate the possibility to independently control the carrier densities in both layers using top and bottom gates, despite there being only a nano-meter scale separation between them.

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H. Schmidt, T. Luedtke, P. Barthold, E. McCann, V. I. Falko, R. J. Haug. 2008-09-29. Tunable Graphene System with Two Decoupled Monolayers. https://doi.org/10.1063/1.3012369

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