The two-dimensional Hubbard model is studied by use of composite operator approach. A set of self-consistent equations for the fermion propagator is derived in a generalized mean field approximation. Preliminary results show a good agreement with the exact results obtained by numerical simulation on ...
mean field theoriesHubbard modelsquare latticetriangular latticespin-boson slave-fermion mean field theoriesHartree-Fock mean field theoryxy-SPIRAL spine order/ A7420 Theory of superconductivity A7470V Perovskite phase superconductorsWe summarize some of the results we have obtained in our recent studies ...
three-body interactionsGutzwiller ansatzThe zero temperature properties of the generalized Bose-Hubbard model including three-body interactions are studied on a mean-field level. We obtain analytical results using the so-called perturbative mean-field method and more detailed numerical results using the ...
Using functional techniques, the Hubbard model consisting of self-coupled lattice fermions is transformed into a bosonic functional integral. In this form it is treated by a mean field approximation in its modern version as a systematic expansion around a saddle point. The method is generalized to...
In this paper a mean-field theory for the spin-liquid paramagnetic non-superconducting phase of the p- and n-type high-Tc cuprates is developed... M.,M.,KorshunovS.,... - 《European Physical Journal B》 被引量: 77发表: 2007年 Does Simple Two-Dimensional Hubbard Model Account for Hi...
This chapter is devoted to applications of the mean-field approximation in metals. We confine the presentation to the Hubbard model, which is relevant to the narrow-band metals. This way we avoid unnecessary technicalities and make a link with further chapters.DOI...
A new mean field theory is proposed for the Mott transition in the Hubbard model based on the slave rotor representation of the electron operator. This theory provides a better description of the role of the long range charge correlation in the Mott insulating state and offers a good estimation...
We investigate the possibility of superconductivity in the large-U limit of the Hubbard model near half filling, using a slave-boson representation. The local constraint is treated in a novel way, incorporating short-range fluctuations in addition to the global constraint. We find slave-boson pairi...
摘要: We construct a new effective two-dimensional Hubbard model by taking the different electron occupancy on site into account. The mean field state of the new Hamiltonian gives rise to the gossamer superconducting state proposed by Laughlin recently(cond-mat/0209269)....
Beyond extended dynamical mean-field theory: Dual boson approach to the two-dimensional extended Hubbard model The dual boson approach [Ann. Phys. 327, 1320 (2012)] provides a means to construct a diagrammatic expansion around the extended dynamical mean-field theor... EGCPV Loon,AI Lichtenstein...