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Properties of Gutzwiller wave-functions for multi-band models

Claudio Attaccalite·Michele Fabrizio
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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 Bünemann, 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.

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Claudio Attaccalite, Michele Fabrizio. 2003-04-08. Properties of Gutzwiller wave-functions for multi-band models. https://doi.org/10.1103/physrevb.68.155117

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