Coulomb Gaps in One-Dimensional Spin-Polarized Electron Systems

TL;DR

This paper studies how Coulomb interactions and disorder affect the density of states near the Fermi energy in one-dimensional spin-polarized electron systems, revealing a power-law behavior influenced by disorder.

Contribution

It introduces a self-consistent Hartree-Fock approach to analyze the interplay of Coulomb gaps and disorder in 1D electron systems near the Fermi energy.

Findings

The density of states follows a power law near the Fermi energy.

The power-law exponent decreases as disorder strength increases.

The Coulomb gap and Wigner lattice gap can coincide at the Fermi energy.

Abstract

We investigate the density of states (DOS) near the Fermi energy of one-dimensional spin-polarized electron systems in the quantum regime where the localization length is comparable to or larger than the inter-particle distance. The Wigner lattice gap of such a system, in the presence of weak disorder, can occur precisely at the Fermi energy, coinciding with the Coulomb gap in position. The interplay between the two is investigated by treating the long-range Coulomb interaction and the random disorder potential in a self-consistent Hartree-Fock approximation. The DOS near the Fermi energy is found to be well described by a power law whose exponent decreases with increasing disorder strength.