Interplay of Mott transition and ferromagnetism in the orbitally degenerate Hubbard model
نویسندگان
چکیده
A slave-boson representation for the degenerate Hubbard model is introduced. The location of the metalto-insulator transition that occurs at commensurate densities is shown to depend weakly on the band degeneracy M . The relative weights of the Hubbard subbands depend strongly on M , as well as the magnetic properties. It is also shown that a sizable Hund’s rule coupling is required in order to have a ferromagnetic instability appearing. The metal-to-insulator transition driven by an increase in temperature is a strong function of it. @S0163-1829~97!02144-9#
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