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Orbital-selective Mott-Hubbard transition in the two-band Hubbard model

R. Arita·K. Held
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Abstract

Recent advances in the field of quantum Monte Carlo simulations for impurity problems allow --within dynamical mean field theory-- for a more thorough investigation of the two-band Hubbard model with narrow/wide band and SU(2)-symmetric Hund's exchange. The nature of this transition has been controversial, and we establish that an orbital-selective Mott-Hubbard transition exists. Thereby, the wide band still shows metallic behavior after the narrow band became insulating -not a pseudogap as for an Ising Hund's exchange. The coexistence of two solutions with metallic wide band and insulating or metallic narrow band indicates, in general, first-order transitions.

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R. Arita, K. Held. 2006-01-27. Orbital-selective Mott-Hubbard transition in the two-band Hubbard model. https://doi.org/10.1103/physrevb.72.201102

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