Properties of Gutzwiller wave-functions for multi-band models

TL;DR

This paper investigates the properties of Gutzwiller wave-functions in multi-band Hubbard models, focusing on the Mott transition and the limitations of these wave-functions in capturing quasi-particle behavior near the transition.

Contribution

It extends the Gutzwiller wave-function to include broken-symmetry phases and critically analyzes its effectiveness in describing Mott transitions in multi-band models.

Findings

Gutzwiller wave-functions have limitations near the Mott transition.

The extended wave-function allows analytical treatment of broken-symmetry phases.

Identifies drawbacks in Gutzwiller wave-functions for quasi-particle properties.

Abstract

We analyze the Mott transition in multi-band Hubbard models with the inclusion of multiplet exchange splittings as it arises in infinite dimensions by using the generalized Gutzwiller wave-function introduced by B\"unemann, Weber and Gebhard [Phys. Rev. B 57, 6896 (1998)]. We also present an extension of that variational wave-function to account for broken-symmetry phases, which still allows an exact analytical treatment. Our analysis reveals some drawbacks of the variational wave-function, which, in our opinion, imply that Gutzwiller-type of wave-functions do not properly capture quasi-particle properties close to a Mott transition.