Combining dynamical mean-field theory and realistic bandstructure of V2O3

TL;DR

This paper combines realistic bandstructure calculations with dynamical mean-field theory to explain magnetic fluctuations and the metal-insulator transition in V2O3, highlighting the role of Fermi surface topology and electron correlations.

Contribution

It introduces a combined approach using Slater-Koster bandstructure and DMFT to analyze magnetic and electronic properties of V2O3, providing new insights into its phase transitions.

Findings

Magnetic fluctuations are driven by Fermi surface topology.

Electron-electron interactions induce the metal-insulator transition.

Orbital ordering is involved in the antiferromagnetic insulator phase.

Abstract

Recent neutron scattering experiments on V2O3 show that the magnetic fluctuations on the metallic side of the antiferromagnetic metal-insulator transition are not related to the spin structure of the insulator, but rather to the bandstructure-driven spin-density wave phase of the doped system V(2-y)O3. We calculate these magnetic fluctuations starting from a Slater-Koster bandstructure and incorporating the correlation effects through the dynamical mean-field theory (DMFT). Our results demonstrate that the magnetic properties of the paramagnetic metallic phase are dominated by the Fermi surface topology. On the other hand, the electron-electron interaction drives the paramagnetic metal-insulator transition in V2O3. The transition to the antiferromagnetic insulator by virtue of orbital ordering is discussed in the framework of the DMFT.