Thermally excited multiband conduction in LaAlO₃/SrTiO ₃ heterostructures exhibiting magnetic scattering

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 electronlike charge carriers. At intermediate temperatures, we observe nonlinear Hall resistance and positive magnetoresistance, establishing the presence of at least two electronlike 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.