Ferromagnetism of the Hubbard Model at Strong Coupling in the Hartree-Fock Approximation

Details Ferromagnetism of the Hubbard Model at Strong Coupling in the Hartree-Fock Approximation Ferromagnetism of the Hubbard Model at Strong Coupling in the Hartree-Fock Approximation

2005-06-27

arxiv.org/abs/cond-mat/0506695v2

Reviews in Mathematical Physics, vol. 18 , no. 5, pp. 519-543 (2006)

Physics

Condensed Matter

Strongly Correlated Electrons

v2: Published version. 30 pages latex. Changes in title, abstract, introduction

Scientific paper

10.1142/S0129055X06002735

As a contribution to the study of Hartree-Fock theory we prove rigorously that the Hartree-Fock approximation to the ground state of the d-dimensional Hubbard model leads to saturated ferromagnetism when the particle density (more precisely, the chemical potential mu) is small and the coupling constant U is large, but finite. This ferromagnetism contradicts the known fact that there is no magnetization at low density, for any U, and thus shows that HF theory is wrong in this case. As in the usual Hartree-Fock theory we restrict attention to Slater determinants that are eigenvectors of the z-component of the total spin, {S}_z = sum_x n_{x,\uparrow} - n_{x,\downarrow}, and we find that the choice 2{S}_z = N = particle number gives the lowest energy at fixed 0 < mu < 4d.

Affiliated with

Also associated with

No associations

Rating

Ferromagnetism of the Hubbard Model at Strong Coupling in the Hartree-Fock Approximation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ferromagnetism of the Hubbard Model at Strong Coupling in the Hartree-Fock Approximation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ferromagnetism of the Hubbard Model at Strong Coupling in the Hartree-Fock Approximation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-645973