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arXiv · 1510.07896

Gutzwiller variational wave function for multi-orbital Hubbard models in finite dimensions

Kevin zu Münster·Jörg Bünemann
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Abstract

We develop a diagrammatic method for the evaluation of general multi-band Gutzwiller wave functions in finite dimensions. Our approach provides a systematic improvement of the widely used Gutzwiller approximation. As a first application we investigate itinerant ferromagnetism and correlation-induced deformations of the Fermi surface for a two-band Hubbard model on a square lattice.

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Kevin zu Münster, Jörg Bünemann. 2015-10-27. Gutzwiller variational wave function for multi-orbital Hubbard models in finite dimensions. https://doi.org/10.1103/physrevb.94.045135

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