One-dimensional physics in transition-metal nanowires: Phases and elementary excitations

TL;DR

This paper classifies possible electronic phases in transition-metal nanowires using Hartree-Fock approximation, highlighting the influence of orbital degeneracy and local spin configurations on the emergence of various density wave and superconducting states.

Contribution

It provides a theoretical classification of phases in transition-metal nanowires considering orbital degeneracy and spin interactions, extending understanding of their elementary excitations.

Findings

Spin density wave and triplet superconductivity favored with high-spin interactions.

Orbital density wave and singlet superconductivity occur with low-spin interactions.

The study offers a phase diagram based on interaction types and spin configurations.

Abstract

We used the Hartree-Fock approximation to classify the electronic phases that might occur in a transition metal nanowire. The important features of this situation are orbital degeneracy (or near-degeneracy) and interactions favoring locally high-spin configurations. In this circumstance, spin density wave and triplet superconductivity states are favored. If the interactions favor locally low-spin configurations as in the previously studied spin ladder systems, orbital density wave and singlet superconductivity are observed.