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Mott transitions in the multi-orbital systems

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

We investigate the Mott transitions in the two-orbital Hubbard model with different bandwidths. By combining dynamical mean field theory with the exact diagonalization, 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. In particular, it is clarified that the $xy$ and pair-hopping components of the Hund coupling play a key role to control the nature of the Mott transitions.

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Akihisa Koga, Norio Kawakami, T. M. Rice, Manfred Sigrist. 2004-06-20. Mott transitions in the multi-orbital systems. https://doi.org/10.1016/j.physb.2005.01.414

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