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arXiv · 1311.3341

Hybridizing localized and itinerant electrons: a recipe for pseudogaps

E. A. Winograd·L. de' Medici
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Abstract

In a system where selective Mott localization is realized, some electrons show a gap to charge excitations while others do not. A hybridization between these two kind of electrons will lead to a smoothening of this sharp difference and can even bring the system back to a complete delocalization. We show here that there is a large region of parameters at finite hybridization where the selective localization persists and the system shows a partial filling of the selective gap with incoherent states, giving rise to a pseudogap. This result is illustrated here in a two orbital Hubbard model with Hund's coupling, but is based on quite general assumptions and should hold for a larger class of systems, and possibly be a paradigm for the pseudogap mechanism in cuprates.

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E. A. Winograd, L. de' Medici. 2014-03-04. Hybridizing localized and itinerant electrons: a recipe for pseudogaps. https://doi.org/10.1103/physrevb.89.085127

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