Charge and spin density waves: Quasi one dimension to two dimension

TL;DR

This paper explores the emergence of charge and spin density waves in quasi-one-dimensional and two-dimensional electron systems, demonstrating these phenomena can occur without Coulomb interactions, primarily driven by Fermi statistics.

Contribution

It shows that charge and spin density waves can arise in quasi-one-dimensional and two-dimensional systems solely due to Fermi statistics, without the need for Coulomb interactions.

Findings

Charge and spin density waves can occur in quasi-one-dimensional systems without Coulomb interactions.

Transition to density waves is shown in two-dimensional systems under certain conditions.

Coulomb interactions are not necessary for the formation of these density waves in the studied regimes.

Abstract

Possibility of electronic charge and spin separation leading to charge density wave and spin density wave is well established in one dimensional systems in presence and absence of Coulomb interaction. We start from quasi one dimension and show the possibility of such a transition in quasi one dimension as well as in two dimension by going to a regime where it can be shown for free electrons that just interact via Fermi statistics. Since Coulomb interaction can only facilitate the phenomenon, the purpose of our work is to show the phenomena unambiguously in the limit when Coulomb interaction can be ignored. Finally we also comment on dimensions greater than two and inclusion of Coulomb interactions.