Tunable Graphene System with Two Decoupled Monolayers

TL;DR

This paper reports on the development of graphene-based FETs with two decoupled monolayers, allowing independent control of carrier densities in each layer, which differs significantly from single-crystal bilayer devices.

Contribution

It introduces a novel fabrication method for decoupled graphene monolayers from a single exfoliation, enabling independent electronic control in FETs.

Findings

Independent control of carrier densities in two layers

Distinct transport characteristics from bilayer graphene

Feasibility of using folded graphene for nanoelectronic devices

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.