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arXiv · 2304.03034

Attraction versus repulsion between doublons or holons in Mott-Hubbard systems

Friedemann Queisser·Gernot Schaller·Ralf Schützhold
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Abstract

For the Mott insulator state of the Fermi-Hubbard model in the strong-coupling limit, we study the interaction between quasi-particles in the form of doublons and holons. Comparing different methods -- the hierarchy of correlations, strong-coupling perturbation theory, and exact analytic solutions for the Hubbard tetramer -- we find an effective interaction between doublons and/or holons to linear order in the hopping strength $T$ which can display attractive as well as repulsive contributions, depending on the involved momenta. Finally, we speculate about the implications of our findings for high-temperature superconductivity.

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Friedemann Queisser, Gernot Schaller, Ralf Schützhold. 2023-04-06. Attraction versus repulsion between doublons or holons in Mott-Hubbard systems. https://doi.org/10.1007/s10773-023-05484-9

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