https://doi.org/10.1140/epjb/e2004-00388-1
The Gutzwiller wave function as a disentanglement prescription
Department of Physics, Faculty of Science,
University of Zagreb, Bijenička cesta 32, HR-10000 Zagreb, Croatia
Corresponding author: a dks@phy.hr
Received:
22
December
2003
Revised:
3
October
2004
Published online:
23
December
2004
The Gutzwiller variational wave function is shown to correspond to a
particular disentanglement of the thermal evolution operator, and to be
physically consistent only in the temperature range 
, the
Fermi energy of the non-interacting system. The correspondence is established
without using the Gutzwiller approximation. It provides a systematic
procedure for extending the ansatz to the strong-coupling regime. This is
carried out to infinite order in a dominant class of commutators. The
calculation shows that the classical idea of suppressing double occupation
is replaced at low temperatures by a quantum RVB-like condition, which
involves phases at neighboring sites. Low-energy phenomenologies are
discussed in the light of this result.
PACS: 71.10.Fd – Lattice fermion models (Hubbard model, etc.) / 71.27.+a – Strongly correlated electron systems; heavy fermions / 71.30.+h – Metal-insulator transitions and other electronic transitions
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004
