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arXiv · 1310.4391

Exact Results on Itinerant Ferromagnetism in Multi-orbital Systems on Square and Cubic Lattices

Yi Li·Elliott H. Lieb·Congjun Wu
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Abstract

We study itinerant ferromagnetism in multi-orbital Hubbard models in certain two-dimensional square and three-dimensional cubic lattices. In the strong coupling limit where doubly occupied orbitals are not allowed, we prove that the fully spin-polarized states are the unique ground states, apart from the trivial spin degeneracies, for a large region of fillings factors. Possible applications to p-orbital bands with ultra-cold fermions in optical lattices, and electronic 3d-orbital bands in transition-metal oxides, are discussed.

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Yi Li, Elliott H. Lieb, Congjun Wu. 2014-04-30. Exact Results on Itinerant Ferromagnetism in Multi-orbital Systems on Square and Cubic Lattices. https://doi.org/10.1103/physrevlett.112.217201

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