Interaction reconstructed integer quantized Hall effect topological insulator

TL;DR

This paper investigates how Coulomb interactions affect the robustness of the integer quantum Hall effect in topological insulators, showing that quantization persists due to interaction-induced incompressible strips and predicting finite impedance between contacts.

Contribution

It introduces a self-consistent model demonstrating the survival of quantized Hall conductance despite topological distortions and potential fluctuations.

Findings

Quantized Hall effect persists with topological distortions.

Finite impedance exists between contacts even in plateau regimes.

Impedance decreases with increasing temperature.

Abstract

We discuss the role of direct Coulomb interaction on the bulk insulator of the integer quantized Hall effect that bridges the topological insulators and the conductance quantization. We investigate the magneto-transport properties of a two-dimensional electron system in the bulk, numerically, utilizing the self-consistent Thomas-Fermi-Poisson screening theory. Topologically distorted Hall bars with and without potential fluctuations are considered that comprises two identical inner contacts. Although these contacts change the topology, we show that quantized Hall effect survives due to redistributed incompressible strips on account of interactions. It is shown phenomenologically that the impedance between these contacts can be obtained by a minimal transport model. An important prediction of our self-consistent approach is a finite impedance between the inner contacts even in the plateau regime, where the maximum of the impedance decreases with increasing temperature.