A supersymmetric mean-field approach to the infinite-U Hubbard model
  A generalized supersymmetric representation of the Hubbard operator algebra is considered. This representation is applied to the infinite-U Hubbard model. A mean-field theory which takes into account both on-site and inter-site virtual boson-fermion transitions is developed. Unlike previous approaches, the mean-field theory considered is free from divergences. Possible application of these results to the ferromagnet-paramagnet transition, as well as to other problems is discussed. 
V.Yu.Irkhin and A.A.Katanin