Topological defects in the edge state structure in a bilayer electron system

TL;DR

This paper reports the first experimental observation of point-like topological defects in the edge state structure of a bilayer electron system within the quantum Hall regime, revealing new insights into edge state interactions.

Contribution

It introduces the experimental detection of topological defects in edge states of bilayer systems and explores their formation and properties under various magnetic field conditions.

Findings

Flattening of I-V curves at specific filling factors

Recovery of nonlinear I-V characteristics in tilted fields

Evidence for topological defects in edge state structures

Abstract

We experimentally demonstrate, for the first time, formation of point-like topological defects in the edge state structure in the quantum Hall effect regime. By using of a selective population technique, we investigate equilibration processes between the edge states in bilayer electron structures with a high tunnelling rate between layers. Unexpected flattening of the I-V curves in perpendicular magnetic field at a specific filling factor combination and the recovery of the conventional nonlinear I-V characteristics in tilted fields give a strong evidence for the existence of topological defects.