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Orbital-selective Mott transitions in the degenerate Hubbard model

Akihisa Koga·Norio Kawakami·T. M. Rice·Manfred Sigrist
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Abstract

We investigate the Mott transitions in two-band Hubbard models with different bandwidths. Applying dynamical mean field theory, we discuss the stability of itinerant quasi-particle states in each band. We demonstrate that separate Mott transitions occur at different Coulomb interaction strengths in general, which merge to a single transition only under special conditions. This kind of behavior may be relevant for the physics of the single-layer ruthenates, Ca$_{2-x}$Sr$_x$RuO$_4$.

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Akihisa Koga, Norio Kawakami, T. M. Rice, Manfred Sigrist. 2004-01-13. Orbital-selective Mott transitions in the degenerate Hubbard model. https://doi.org/10.1103/physrevlett.92.216402

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