Excitonic insulators as a model of $d-d$ and Mott transitions in strongly correlated materials
arXiv:1708.02270
Abstract
We show how strongly correlated materials could be described within the framework of an excitonic insulator formalism, and delineate the relationship between inter- and intra-band ordering phenomena. Our microscopic model of excitons clarifies the fundamental role of Van-Hove-singularity-nesting in driving both inter- and intra-band ordering transitions, and uncovers an interesting connection with resonating-valence-bond physics.
11 pages, 5 figures