Ferromagnetic ground state in the Kondo lattice model

  • S.-Q. Shen


We present a series of rigorous examples of the Kondo lattice model that exhibit full ferromagnetism in the ground state. The models are defined in one-, two- and three-dimensional lattices, and are characterized by a range of hopping terms, specific electron filling, and large ferromagnetic coupling. Our examples show that a sufficient strong but finite exchange coupling between conduction electrons and localized spins could overcome the competition from mobility of a finite density of electrons and drive the system from a paramagnetic phase to a ferromagnetic phase. We also establish a relation of ferromagnetism between the Hubbard model and Kondo lattice model. Meanwhile some rigorous results on ferromagnetism in the corresponding Hubbard model are presented.

PACS. 75.10.Lp Band and itinerant models - 75.50.-y Studies of specific magnetic materials 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© EDP Sciences, Springer-Verlag 1998

Authors and Affiliations

  • S.-Q. Shen
    • 1
  1. 1.Department of PhysicsThe University of Hong KongHong Kong

Personalised recommendations