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Journal of Statistical Physics

, Volume 118, Issue 5–6, pp 973–978 | Cite as

Hund’s Rule and Metallic Ferromagnetism

  • Jürg Fröhlich
  • Daniel Ueltschi
Article

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.

Keywords

Metallic Ferromagnetism Hund’s rule two-band tight-binding models 

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Copyright information

© Springer Science+Business media, Inc. 2005

Authors and Affiliations

  1. 1.Institut Für Theroretische PhysikEidgenössische Technische HochschuleZürichSwitzerland
  2. 2.Department of MathematicsUniversity of ArizonaTucsonUSA

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