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Phase diagram of the Mott Transition in a two-band Hubbard model in infinite dimensions

Y. Ono·R. Bulla·A. C. Hewson
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Abstract

The Mott metal-insulator transition in the two-band Hubbard model in infinite dimensions is studied by using the linearized dynamical mean-field theory recently developed by Bulla and Potthoff. The phase boundary of the metal-insulator transition is obtained analytically as a function of the on-site Coulomb interaction at the $d$-orbital, the charge-transfer energy between the $d$- and $p$-orbitals and the hopping integrals between $p-d$, $d-d$ and $p-p$ orbitals. The result is in good agreement with the numerical results obtained from the exact diagonalization method.

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Y. Ono, R. Bulla, A. C. Hewson. 2001-03-15. Phase diagram of the Mott Transition in a two-band Hubbard model in infinite dimensions. https://doi.org/10.1007/s100510170313

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