General Approach to the Quasiparticle Description of Strongly Correlated Systems

M. Grilli, Roberto Raimondi

H. V. Grushevskaya

Sergei G. Ovchinnikov, Valerii Vladimirovich Val'kov

Hubbard Model as the Simplest Model of Strong Electron Correlation Multielectron Models in X-Operators Representation General Approach to the Quasiparticle Description of Strongly Correlated Systems Unitary Transformations Method in Atomic Representation Diagram Technique in the X-Operators Representation Spectral Properties of the Anisotropic Metallic Ferromagnets Peculiarities of the de Haas-van Alphen Effect in Strongly Correlated Systems with Magnetic Polaron States The Electronic Structure of Copper Oxides in the Multiorbital p-d Model

VICTOR A. KHODEL, J. W. Clark, MIKHAIL V. ZVEREV

M. M. Korshunov, S. G. Ovchinnikov

By on the analyzing the general structure of the Green function of a strongly correlated electron system, it is shown that, for the regime of strong correlations, Luttinger’s theorem should be generalized in the following way: the volume of the Fermi surface of the system of noninteracting particles is equal to that of the quasiparticles in the strongly correlated system with due regard for the spectral weight of the quasiparticles. An investigation of the t-J model and of the Hubbard model, as applied to the paramagnetic nonsuperconducting phase, shows that the generalized Luttinger theorem is valid for these models.