STRONG COUPLING HARTREE-FOCK APPROXIMATION IN THE DYNAMICAL MEAN-FIELD THEORY
Andrij M. Shvaika
In the limit of infinite spatial dimensions, a thermodynamically consistent theory, which is valid for arbitrary value of the Coulombic interaction ( U < ∞ ), is built for the Hubbard model when the total auxiliary single-site problem exactly splits into four subspaces with different "vacuum states".Some analytical results are given for the Hartree-Fock approximation when the 4pole structure for Green's function is obtained: two poles describe contribution from the Fermi liquid component, which is ferromagnetic and dominant for small electron and hole concentrations ("overdoped case" of high-T c 's), whereas other two describe contribution from the non-Fermi liquid, which is antiferromagnetic and dominant close to half filling ("underdoped case").
arXiv:cond-mat/0011407•Condensed Matter Physics•Jan 1, 2001•1 citation