Journal of Physics C Solid State Physics

On the ground state phase diagram of the Hubbard model

Andrzej M. Oleś

Published Oct 30, 1982• 16 citations

Abstract

Magnetic ordering of the Hubbard model is investigated with the help of a variational ansatz for the ground state. It is shown that only antiferromagnetic and special ferromagnetic states are stable against the paramagnetic one for the band fillings n close to n=1 and sufficiently strong Coulomb interaction.

DOI: 10.1088/0022-3719/15/30/004

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