Hubbard fermions band splitting at the strong intersite Coulomb interaction

Abstract

The effect of the strong intersite Coulomb correlations on the formation of the electron structure of the t-V-model has been studied. A qualitatively new result has been obtained which consists in the occurrence of a split-off band of the Fermi states. The spectral intensity of this band increases with the enhancement of a doping level and is determined by the mean-square fluctuation of the occupation numbers. This leads to the qualitative change in the structure of the electron density of states.