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Magnetic Doublon Bound States in the Kondo Lattice Model

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 نشر من قبل Roman Rausch
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present a novel pairing mechanism for electrons, mediated by magnons. These paired bound states are termed magnetic doublons. Applying numerically exact techniques (full diagonalization and the density-matrix renormalization group, DMRG) to the Kondo lattice model at strong exchange coupling $J$ for different fillings and magnetic configurations, we demonstrate that magnetic doublon excitations exist as composite objects with very weak dispersion. They are highly stable, support a novel inverse colossal magnetoresistance and potentially other effects.

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