In this work we investigate an unusual transport phenomenon observed intwo-dimensional electron gas under integer quantum Hall effect conditions. Ourcalculations are based on the screening theory, using a semi-analytical model.The transport anomalies are \emph{dip} and overshoot effects, where the Hallresistance decreases (or increases) unexpectedly at the quantized resistanceplateaus intervals. We report on our numerical findings of the \emph{dip}effect in the Hall resistance, considering GaAs/AlGaAs heterostructures inwhich we investigated the effect under different experimental conditions. Weshow that, similar to overshoot, the amplitude of the dip effect is stronglyinfluenced by the edge reconstruction due to electrostatics. It is observedthat the steep potential variation close to the physical boundaries of thesample results in narrower incompressible strips, hence, the experimentalobservation of the dip effect is limited by the properties of these currentcarrying strips. By performing standard Hall resistance measurements on gatedefined narrow samples, we demonstrate that the predictions of the screeningtheory is in well agreement with our experimental findings.
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