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Non-Fermi Liquid Behavior and Double-Exchange Physics in Orbital-Selective Mott Systems

S. Biermann·L. de' Medici·A. Georges
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Abstract

We study a multi-band Hubbard model in its orbital selective Mott phase, in which localized electrons in a narrow band coexist with itinerant electrons in a wide band. The low-energy physics of this phase is shown to be closely related to that of a generalized double-exchange model. The high-temperature disordered phase thus differs from a Fermi liquid, and displays a finite scattering rate of the conduction electrons at the Fermi level, which depends continuously on the spin anisotropy.

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S. Biermann, L. de' Medici, A. Georges. 2005-06-02. Non-Fermi Liquid Behavior and Double-Exchange Physics in Orbital-Selective Mott Systems. https://doi.org/10.1103/physrevlett.95.206401

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