1 research outputs found
The dip effect under integer quantized Hall conditions
In this work we investigate an unusual transport phenomenon observed in two-dimensional
electron gas under integer quantum Hall effect conditions. Our calculations are based on
the screening theory, using a semi-analytical model. The transport anomalies are dip and
overshoot effects, where the Hall resistance decreases (or increases) unexpectedly at the
quantized resistance plateaus intervals. We report on our numerical findings of the dip
effect in the Hall resistance, considering GaAs/AlGaAs heterostructures in which we
investigated the effect under different experimental conditions. We show that, similar to
overshoot, the amplitude of the dip effect is strongly influenced by the edge
reconstruction due to electrostatics. It is observed that the steep potential variation
close to the physical boundaries of the sample results in narrower incompressible strips,
hence, the experimental observation of the dip effect is limited by the properties of
these current carrying strips. By performing standard Hall resistance measurements on gate
defined narrow samples, we demonstrate that the predictions of the screening theory is in
well agreement with our experimental findings