Gutzwiller-correlated wave functions for degenerate bands: exact results in infinite dimensions

TL;DR

This paper develops an exact analytical framework for Gutzwiller-correlated wave functions in multi-band Hubbard models in infinite dimensions, confirming the accuracy of the Gutzwiller approximation and Slave Boson theory in this limit.

Contribution

It introduces a diagrammatic formalism for evaluating ground-state properties and demonstrates the exactness of the Gutzwiller approximation and Slave Boson theory in infinite dimensions.

Findings

Gutzwiller wave functions yield exact results in infinite dimensions.

Slave Boson mean-field theory becomes variationally controlled at zero temperature.

The approach provides insights into the Anderson transition in strongly correlated systems.

Abstract

We introduce Gutzwiller-correlated wave functions for the variational investigation of general multi-band Hubbard models. We set up a diagrammatic formalism which allows us to evaluate analytically ground-state properties in the limit of infinite spatial dimensions. In this limit recent results obtained within the Gutzwiller approximation are seen to become exact for these wave functions. We further show that the Slave Boson mean-field theory for degenerate bands becomes variationally controlled at zero temperature in infinite dimensions. Lastly, we briefly comment on the variational approach to the Anderson transition in strongly correlated electron systems.