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arXiv · 0705.3318

Orbital order in degenerate Hubbard models : A variational study

Joerg Buenemann·Katalin Javorne-Radnoczi·Patrik Fazekas·Florian Gebhard
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Abstract

We use the Gutzwiller variational many-body theory to investigate the stability of orbitally ordered states in a two-band Hubbard-model without spin degrees of freedom. Our results differ significantly from earlier Hartree-Fock calculations for this model. The Hartree-Fock phase diagram displays a large variety of orbital orders. In contrast, in the Gutzwiller approach orbital order only appears for densities in a narrow region around half filling.

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Joerg Buenemann, Katalin Javorne-Radnoczi, Patrik Fazekas, Florian Gebhard. 2007-09-10. Orbital order in degenerate Hubbard models : A variational study. https://doi.org/10.1088/0953-8984%2F19%2F32%2F326217

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