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arXiv · 1909.11896

Magnetic Doublon Bound States in the Kondo Lattice Model

Roman Rausch·Michael Potthoff·Norio Kawakami
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Abstract

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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Roman Rausch, Michael Potthoff, Norio Kawakami. 2019-09-26. Magnetic Doublon Bound States in the Kondo Lattice Model. https://doi.org/10.1103/physrevlett.123.216401

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