Exact ground state in an orbitally degenerate Hubbard model
نویسندگان
چکیده
منابع مشابه
The ground state phases of orbitally degenerate spinel oxides
I review the microscopic spin-orbital Hamiltonian and ground state properties of spin one-half spinel oxides with threefold t2g orbital degeneracy. It is shown that for any orbital configuration a ground state of corresponding spin only Hamiltonian is infinitely degenerate in the classical limit. The extensive classical degeneracy is lifted by the quantum nature of the spins, an effect similar ...
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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...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 1998
ISSN: 0163-1829,1095-3795
DOI: 10.1103/physrevb.57.6474