The Quantum Hall Effect and Inter-edge State Tunneling Within a Barrier

TL;DR

This paper investigates how a nano-scale incursion into a potential barrier affects conductance in a quantum Hall system, revealing quantized plateaus, minima, and oscillations due to edge and localized state tunneling.

Contribution

It introduces a controllable nano-scale incursion into a quantum Hall barrier and analyzes the resulting tunneling phenomena and conductance features.

Findings

Observation of quantized conductance plateaus.

Identification of minima and oscillations in conductance.

Explanation of features as tunneling between edge and localized states.

Abstract

We have introduced a controllable nano-scale incursion into a potential barrier imposed across a two-dimensional electron gas, and report on the phenomena that we observe as the incursion develops. In the quantum Hall regime, the conductance of this system displays quantized plateaus, broad minima and oscillations. We explain these features and their evolution with electrostatic potential geometry and magnetic field as a progression of current patterns formed by tunneling between edge and localized states within the barrier.