Hund's rule and metallic ferromagnetism
arXiv:cond-mat/0404483 · doi:10.1007/s10955-004-2174-y
Abstract
We study tight-binding models of itinerant electrons in two different bands, with effective on-site interactions expressing Coulomb repulsion and Hund's rule. We prove that, for sufficiently large on-site exchange anisotropy, all ground states show metallic ferromagnetism: They exhibit a macroscopic magnetization, a macroscopic fraction of the electrons is spatially delocalized, and there is no energy gap for kinetic excitations.
17 pages
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Cited by in corpus (5)
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- Anderson Localization Triggered by Spin Disorder---with an Application to Eu_x Ca_1-x B_6