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arXiv · 1311.5807

Thermally excited multi-band conduction in LaAlO3/SrTiO3 heterostructures exhibiting magnetic scattering

V. K. Guduru·A. McCollam·A. Jost·S. Wenderich·H. Hilgenkamp·J. C. Maan·A. Brinkman·U. Zeitler
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Abstract

Magnetotransport measurements of charge carriers at the interface of a LaAlO3/SrTiO3 heterostructure with 26 unit cells of LaAlO3 show Hall resistance and magnetoresistance which at low and high temperatures is described by a single channel of electron-like charge carriers. At intermediate temperatures, we observe non-linear Hall resistance and positive magnetoresistance, establishing the presence of at least two electron-like channels with significantly different mobilities and carrier concentrations. These channels are separated by 6 meV in energy and their temperature dependent occupation and mobilities are responsible for the observed transport properties of the interface. We observe that one of the channels has a mobility that decreases with decreasing temperature, consistent with magnetic scattering in this channel.

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V. K. Guduru, A. McCollam, A. Jost, S. Wenderich, H. Hilgenkamp, J. C. Maan, A. Brinkman, U. Zeitler. 2013-11-22. Thermally excited multi-band conduction in LaAlO3/SrTiO3 heterostructures exhibiting magnetic scattering. https://doi.org/10.1103/physrevb.88.241301

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