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arXiv · 1701.01819

Mott physics beyond Brinkman-Rice scenario

Marcin M. Wysokinski·Michele Fabrizio
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Abstract

The main flaw of the well-known Brinkman-Rice description, obtained through the Gutzwiller approximation, of the paramagnetic Mott transition in the Hubbard model is in neglecting high-energy virtual processes that generate for instance the antiferromagnetic exchange $J\sim t^2/U$. Here we propose a way to capture those processes by combining the Brinkman-Rice approach with a variational Schrieffer-Wolff transformation, and apply this method to study the single-band metal-to-insulator transition in a Bethe lattice with infinite coordination number, where the Gutzwiller approximation becomes exact. We indeed find for the Mott transition a description very close to the real one provided by dynamical mean-field theory; an encouraging result in view of possible applications to more involved models.

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Marcin M. Wysokinski, Michele Fabrizio. 2017-01-07. Mott physics beyond Brinkman-Rice scenario. https://doi.org/10.1103/physrevb.95.161106

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