Metal-insulator transition in VO$_{2}$: a Peierls-Mott-Hubbard mechanism

TL;DR

This study investigates the metal-insulator transition in VO₂, demonstrating that both structural distortion and electron-electron interactions are crucial, with a combined Peierls-Mott-Hubbard mechanism explaining the transition.

Contribution

It provides a quantitative analysis showing that both Peierls and Mott-Hubbard mechanisms are essential for understanding VO₂'s metal-insulator transition.

Findings

Optical gap matches experimental values using LDA+U

Both structural distortion and Coulomb interactions are important

Peierls and Mott-Hubbard mechanisms jointly explain the transition

Abstract

The electronic structure of VO$_2$ is studied in the frameworks of local density approximation (LDA) and LDA+$U$ to give a quantitative description of the metal-insulator (MI) transition in this system. It is found that, both structural distortion and the local Coulomb interaction, play important roles in the transition. An optical gap, comparable to the experimental value has been obtained in the monoclinic structure by using the LDA+$U$ method. Based on our results, we believe that both, the Peierls and the Mott-Hubbard mechanism, are essential for a description of the MI transition in this system.