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Novel Mott Transitions in Non-Isotropic Two-Band Hubbard Model

A. Liebsch
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Abstract

The Mott transition in a two-band Hubbard model involving subbands of different widths is studied as a function of temperature using dynamical mean field theory combined with exact diagonalization. The phase diagram is shown to exhibit two successive first-order transitions if the full Hund's rule coupling is included. In the absence of spin-flip and pair-exchange terms the lower transition remains first-order while the upper becomes continuous.

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A. Liebsch. 2005-07-12. Novel Mott Transitions in Non-Isotropic Two-Band Hubbard Model. https://doi.org/10.1103/physrevlett.95.116402

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