Magnetism induced by electric impurities: A one-body problem with half the physics of the fractional quantum Hall effect

TL;DR

This paper investigates how electric impurities induce magnetism in a 2D electron system, revealing a connection to the fractional quantum Hall effect through spectral analysis and effective magnetic field shifts.

Contribution

It demonstrates a novel link between impurity-induced magnetism and fractional quantum Hall physics using a one-body spectral approach.

Findings

Energy band shifts correspond to half the effective magnetic field in the composite-fermion model.

Impurities cause a downshift in the Landau level spectrum proportional to impurity density.

The results connect impurity effects to fundamental fractional quantum Hall phenomena.

Abstract

We study spectra for a 2D electron in the lowest Landau level with randomly distributed, repulsively correlated electric impurities. The lowest energy band reflects an effective magnetic field downshifted by an integer multiple of the impurity density. The downshift is precisely half that for the corresponding electron density in the composite-fermion picture of the fractional quantum Hall regime.