Colossal non-saturating linear magnetoresistance in two-dimensional electron systems at a GaAs/AlGaAs heterointerface

TL;DR

This paper reports a colossal, non-saturating linear magnetoresistance in 2D electron systems at a GaAs/AlGaAs heterointerface, driven by classical nanoscale inhomogeneities, with potential for on-chip magnetic sensing.

Contribution

It demonstrates a giant NLMR in GaAs/AlGaAs heterostructures at high bias, revealing a classical origin and promising applications in magnetic sensing.

Findings

Magnetoresistance reaches nearly 10,000% at 8 Tesla.

NLMR is driven by nanoscale inhomogeneities and has a classical origin.

Device dimensions and high bias enhance the NLMR effect.

Abstract

Engineering devices with a large electrical response to magnetic field is of fundamental importance for a range of applications such as magnetic field sensing and magnetic read-heads. We show that a colossal non-saturating linear magnetoresistance (NLMR) arises in two-dimensional electron systems hosted in a GaAs/AlGaAs heterostructure in the strongly insulating regime. When operated at high source-drain bias, the magnetoresistance of our devices increases almost linearly with magnetic field reaching nearly 10,000% at 8 Tesla, thus surpassing many known non-magnetic materials that exhibit giant NLMR. The temperature dependence and mobility analysis indicate that the NLMR has a purely classical origin, driven by nanoscale inhomogeneities. A large NLMR combined with small device dimensions makes these systems a new and attractive candidate for on-chip magnetic field sensing.