THE BOSON-FERMION MODEL IN THE MEAN-FIELD APPROXIMATION

The boson-fermion model is studied within the mean-field approximation including Pauli principle effects in the boson energy renormalization and Coulomb short-range repulsion among fermions and bosons. It is sh own that there is a finite critical temperature at which Cooper pairin g occurs accompanied by the divergence of the renormalized boson propa gator at q = 0 and w = 0. The chemical potential, the entropy and the specific heat are also discussed. (C) 1998 Elsevier Science B.V. All r ights reserved.