Gated non-local magnetoresistance measurement in a GaAs/AlGaAs heterostructure
We have made non-local measurements of a two-dimensional electron gas (2DEG) formed at the interface of a GaAs/GaxAl1-xAs heterojunction. The magnetoresistance was measured on a standard Hall bar that had a gate placed between the current and voltage probes. We observed non-local resistance peaks at the location of the Shubnikov-de Haas oscillation maxima. The magnitude of these peaks depends on the gate voltage applied to the semiconductor between the current and voltage probes. We also observe 'Aharanov-Bohm'-like oscillations, presumably due to a localized impurity near the gate.