Graphene on Gallium Arsenide: Engineering the visibility

TL;DR

This paper presents a method to make graphene visible on gallium arsenide (GaAs) by engineering a multi-layer structure, enabling easier identification of graphene layers similar to silicon-based substrates.

Contribution

The authors demonstrate that tailored GaAs/AlAs multilayers render graphene visible under standard microscopy, facilitating studies on graphene-GaAs heterostructures.

Findings

Graphene is visible on GaAs/AlAs structures using standard microscopy.

Raman spectroscopy confirms the layer identification.

The method enables easier exploration of graphene on GaAs.

Abstract

Graphene consists of single or few layers of crystalline ordered carbon atoms. Its visibility on oxidized silicon (Si/SiO\_2) enabled its discovery and spawned numerous studies of its unique electronic properties. The combination of graphene with the equally unique electronic material gallium arsenide (GaAs) has up to now lacked such easy visibility. Here we demonstrate that a deliberately tailored GaAs/AlAs (aluminum arsenide) multi-layer structure makes graphene just as visible on GaAs as on Si/SiO\_2. We show that standard microscope images of exfoliated graphite on GaAs/AlAs suffice to identify mono-, bi-, and multi-layers of graphene. Raman data confirm our results.