Stability of ferromagnetism in a single-band model
Phys. Rev. B 46, 5412 – Published 1 September, 1992
DOI: https://doi.org/10.1103/PhysRevB.46.5412
Abstract
The ground state of the model of single band with on-site Coulomb and intersite exchange interactions between electrons is investigated with the help of a variational ansatz which emphasizes the local character of electron correlations. It is found that the exchange interactions stabilize ferromagnetic solutions but electron correlations reduce the regions of stability of both weak and strong ferromagnetism as compared with the Hartree-Fock approximation. It is argued that the model explains the occurrence of metallic ferromagnetism in metals with a partially filled nondegenerate band, as in metallic hydrogen, but not in transition metals.