Condensed Matter Physics, 2005, vol. 8, No. 4(44), p. 801812, English
DOI:10.5488/CMP.8.4.801
Title:
A generating functional approach to the sdmodel with strong
correlations
Author(s):
 Yu.A.Izyumov
(Institute for Metal
Physics of the RAS, Ural Division 620219 Ekaterinburg, Russia)
,

 N.I.Chaschin
(Institute for Metal
Physics of the RAS, Ural Division 620219 Ekaterinburg, Russia)
,

 D.S.Alexeev
(Institute for Metal
Physics of the RAS, Ural Division 620219 Ekaterinburg, Russia)
,

A KadanoffBaymtype generating functional approach, earlier
developed by the authors to strongly correlated systems, is
applied to the sdmodel with strong sdcoupling. Formalism of the
Hubbard Xoperators was used, and equation for electron Green's
function was derived with functional derivatives over
external fluctuating fields. Iterations in this equation generate
a perturbation theory near the atomic limit. HartreeFock type
approximation is developed within the framework of this theory,
and the problem of a metalinsulator phase transition in sdmodel
is discussed.
Key words:
theories and models of manyelectron systems, lattice
fermion models, strongly correlated electron systems
PACS:
71.10.w, 71.10.Fd, 71.27.+a
