Long-range order in quasi-one-dimensional conductors

TL;DR

This paper investigates how charge-density wave order and superconductivity can be stabilized in quasi-one-dimensional systems through interactions with three-dimensional phonons, disorder, or tunnel coupling.

Contribution

It demonstrates mechanisms for stabilizing long-range order and superconductivity in 1D systems via phonon interactions, disorder, or coupling to 3D metals.

Findings

CDW stabilized by phonons in quasi-1D crystals and nanowires

Phonons alone insufficient for metallic chains; disorder or commensurability needed

Superconductivity possible via tunnel coupling to 3D metals

Abstract

We study formation of the charge-density wave long-range order in a system of repulsive 1D electrons coupled to 3D phonons. We show that the CDW can be stabilized by interaction with phonons in quasi-1D crystals and semiconducting nanowires. In the case of metallic atomic chains, interaction with phonons of 3D substrate is not enough, and violation of the translational invariance by commensurable perturbation or disorder is needed. The possibility of stabilization of superconductivity in 1D electrons with attraction by means of tunnel coupling to a 3D metal is considered.