Magneto-Transport Properties of Exfoliated Graphene on GaAs

TL;DR

This study investigates the magneto-transport properties of exfoliated graphene on GaAs substrates, demonstrating tunable carrier density and observing quantum Hall effects, contributing to understanding graphene's electronic behavior on III-V semiconductors.

Contribution

It presents a method to tune graphene's carrier density on GaAs substrates and studies its magneto-transport properties, including weak localization and quantum Hall effects.

Findings

Successful tuning of graphene carrier density using GaAs back-gate

Observation of quantum Hall effect in exfoliated graphene on GaAs

Detection of weak localization effects in the magnetic field

Abstract

We studied the magneto-transport properties of graphene prepared by exfoliation on a III V semiconductor substrate. Tuneability of the carrier density of graphene was achieved by using a doped GaAs substrate as a back-gate. A GaAs/AlAs multilayer, designed to render the exfoliated graphene flakes visible, also provides the required back-gate insulation. Good tuneability of the graphene carrier density is obtained, and the typical Dirac resistance characteristic is observed despite the limited height of the multilayer barrier compared to the usual SiO2 oxide barrier on doped silicon. In a magnetic field weak localization effects as well as the quantum Hall effect of a graphene monolayer are studied.