Charge density oscillations in a quasi-two-dimensional electron gas for integer filling factors

TL;DR

This paper investigates charge density oscillations in a finite-thickness two-dimensional electron system under strong magnetic fields and integer filling factors, revealing self-consistent oscillatory charge distributions and their experimental signatures.

Contribution

It introduces a self-consistent effective action formalism showing that oscillatory charge density states are energetically favored in such systems.

Findings

Charge density oscillations are generated and stable in the model.

Oscillations have a wave vector accessible to experiments.

Hall voltage and current density oscillate with the same wave vector.

Abstract

The possibility of charge density oscillations in a {\it finite-thickness} two-dimensional system is investigated for strong magnetic fields and integer filling factors. Using an effective action formalism, it is shown that an {\it oscillatory charge density} (OCD) is generated in a self-consistent way and is favored energetically over homogeneous distributions. It is smooth on the scale of the sample thickness and of the magnetic length. The modulus of its wave vector is shown to be experimentally accessible. The Hall voltage and the current density are shown to {\it oscillate} with the same wave vector when a weak current is applied. The stability of the charge oscillations against impurity potentials is discussed.