Perturbation Theory of Strongly Correlated Electrons with and Without Slave Boson Technique

摘要

The Green functions of the electrons in the two-band Hubbard model with the strong on-site Coulomb repulsion were calculated by means of perturbation theory with respect to the hopping term of the Hamiltonian. It was shown that in the slave boson technique we obtain the expressions different from the results of the calculations involving directly electron operators without using slave bosons. The physical meaning of this discrepancy was discussed. (ERA citation 14:023459)