Enhancement of Wigner crystallization in quasi low-dimensional solids

TL;DR

This paper investigates how electron crystallization is enhanced in quasi low-dimensional solids due to Coulomb interactions, revealing structural transitions and stabilization mechanisms for Wigner crystals that relate to charge order phenomena.

Contribution

It introduces a model considering full 3D Coulomb interactions in quasi low-dimensional systems, showing enhanced Wigner crystallization and structural transitions.

Findings

Restriction to layers or chains induces structural transitions.

Low-dimensional electron motion stabilizes Wigner crystals.

Mechanisms may explain charge order in related compounds.

Abstract

The crystallization of electrons in quasi low-dimensional solids is studied in a model which retains the full three-dimensional nature of the Coulomb interactions. We show that restricting the electron motion to layers (or chains) gives rise to a rich sequence of structural transitions upon varying the particle density. In addition, the concurrence of low-dimensional electron motion and isotropic Coulomb interactions leads to a sizeable stabilization of the Wigner crystal, which could be one of the mechanisms at the origin of the charge ordered phases frequently observed in such compounds.