Quantum Hall Resistance Overshoot in 2-Dimensional Electron Gases - Theory and Experiment

TL;DR

This paper investigates the Hall resistance overshoot phenomenon in 2D electron gases under quantum Hall conditions, combining experimental data with a screening theory model to explain the effect.

Contribution

It introduces a comprehensive model based on screening theory that explains the Hall resistance overshoot observed in various material systems under IQHE conditions.

Findings

Experimental observation of Hall resistance overshoot in Si/SiGe heterostructures.

Development of a model attributing overshoot to co-existing evanescent incompressible strips.

The model successfully explains the conditions and mechanisms behind the overshoot phenomenon.

Abstract

We present a systematical experimental investigation of an unusual transport phenomenon observed in two dimensional electron gases in Si/SiGe heterostructures under integer quantum Hall effect (IQHE) conditions. This phenomenon emerges under specific experimental conditions and in different material systems. It is commonly referred to as Hall resistance overshoot, however, lacks a consistent explanation so far. Based on our experimental findings we are able to develop a model that accounts for all of our observations in the framework of a screening theory for the IQHE. Within this model the origin of the overshoot is attributed to a transport regime where current is confined to co-existing evanescent incompressible strips of different filling factors.