Charge Density Wave in Two-Dimensional Electron Liquid in Weak Magnetic Field

TL;DR

This paper investigates the ground state of a two-dimensional electron liquid in a weak magnetic field, revealing a charge density wave with alternating domains and a pseudogap in the density of states that depends linearly on the magnetic field.

Contribution

It demonstrates the formation of a charge density wave with domain structure in a partially filled Landau level and predicts a linear magnetic field dependence of the pseudogap in the density of states.

Findings

Electrons form alternating domains with filling factors 1 and 0.

The domain period is on the order of the cyclotron radius.

The density of states exhibits a pseudogap linearly dependent on magnetic field.

Abstract

We study the ground state of a clean two-dimensional electron liquid in a weak magnetic field where $N \gg 1$ lower Landau levels are completely filled and the upper level is partially filled. It is shown that the electrons at the upper Landau level form domains with filling factor equal to one and zero. The domains alternate with a spatial period of order of the cyclotron radius, which is much larger than the interparticle distance at the upper Landau level. The one-particle density of states, which can be probed by tunneling experiments, is shown to have a pseudogap linearly dependent on the magnetic field in the limit of large $N$.