Transport in strongly-coupled graphene-LaAlO3/SrTiO3 hybrid systems

TL;DR

This study investigates the transport properties of hybrid graphene-LaAlO3/SrTiO3 devices, revealing efficient gating, rectification, and electrostatic effects in strongly-coupled bilayer systems.

Contribution

It provides new insights into the electrostatic and tunneling behaviors in graphene-oxide hybrid systems with potential for electronic applications.

Findings

Efficient reciprocal gating between graphene and oxide layers.

Observation of rectifying behavior at higher bias.

Electrostatic depletion and tunneling effects are significant.

Abstract

We report on the transport properties of hybrid devices obtained by depositing graphene on a LaAlO3/SrTiO3 oxide junction hosting a 4 nm-deep two-dimensional electron system. At low graphene-oxide inter-layer bias the two electron systems are electrically isolated, despite their small spatial separation, and very efficient reciprocal gating is shown. A pronounced rectifying behavior is observed for larger bias values and ascribed to the interplay between electrostatic depletion and tunneling across the LaAlO3 barrier. The relevance of these results in the context of strongly-coupled bilayer systems is discussed.