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arXiv · 1207.5709

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

M. A. Aamir·Srijit Goswami·Matthias Baenninger·Vikram Tripathi·Michael Pepper·Ian Farrer·David A. Ritchie·Arindam Ghosh
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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.

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M. A. Aamir, Srijit Goswami, Matthias Baenninger, Vikram Tripathi, Michael Pepper, Ian Farrer, David A. Ritchie, Arindam Ghosh. 2012-07-24. Colossal non-saturating linear magnetoresistance in two-dimensional electron systems at a GaAs/AlGaAs heterointerface. https://doi.org/10.1103/physrevb.86.081203

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