Two-terminal conductance fluctuations in the integer quantum Hall regime

TL;DR

This paper models conductance fluctuations in mesoscopic quantum Hall systems by incorporating Coulomb interactions into edge-state transport, explaining how localized state occupancies and electrostatic potential variations cause transmission fluctuations.

Contribution

It introduces a numerical model that includes Coulomb interactions affecting edge-state transmission in quantum Hall systems, aligning with experimental observations.

Findings

Coulomb interactions induce conductance fluctuations via localized state occupancy changes.

Electrostatic potential variations cause transmission probability fluctuations.

Model aligns well with recent experimental data.

Abstract

Motivated by recent experiments on the conductance fluctuations in mesoscopic integr quantum Hall systems, we consider a model in which the Coulomb interactions are incorporated into the picture of edge-state transport through a single saddle-point. The occupancies of `classical' localised states in the two-dimensional electron system change due to the interactions between electrons when the gate voltage on top of the device is varied. The electrostatic potential between the localised states and the saddle-point causes fluctuations of the saddle-point potential and thus fluctuations of the transmission probability of edge states. This simple model is studied numerically and compared with the observation.