Multi-orbital Effects in Optical Properties of Vanadium Sesquioxide

TL;DR

This paper investigates the optical properties of V2O3 in its paramagnetic phases using a new theoretical approach, providing insights into temperature-dependent behavior and complementing existing spectral studies.

Contribution

It introduces a generalized Peierls approach to analyze optical properties of V2O3, enhancing understanding of its temperature dependence and many-body effects.

Findings

Results agree overall with experimental data.

Temperature dependence linked to charge carrier coherence scales.

Provides a complementary perspective to photoemission studies.

Abstract

Vanadium sesquioxide, V2O3, boasts a rich phase diagram whose description necessitates the accounting for many-body Coulomb correlations. Spectral properties of this compound have been successfully addressed within dynamical mean field theory to an extent that results of recent angle resolved photoemission experiments have been correctly predicted. While photoemission spectroscopy probes the occupied part of the one-particle spectrum, optical experiments measure transitions into empty states and thus provide complementary information. In this work, we focus on the optical properties of V2O3 in its paramagnetic phases by employing our recently developed "generalized Peierls approach". Compared to experiments, we obtain results in overall satisfactory agreement. Further, we rationalize that the experimentally observed temperature dependence stems from the different coherence scales of the involved charge carriers.