$\eta$-pairing in a two-band model of spinless fermions

Igor N. Karnaukhov

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arXiv · 2604.21318

$\eta$-pairing in a two-band model of spinless fermions

Igor N. Karnaukhov

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Abstract

We study the two-band model of spinless fermions in which itinerant fermions interact with localized fermions through the two-particle hybridization. In 1D version, the model has exact solution using the Bethe ansatz. It has been shown that accounting for two-particle hybridization reduces the repulsive interaction between itinerant fermions. In the case of strong interaction, the effective interaction between itinerant fermions is attractive, and $\eta$-pairing of spinless fermions is realized. The proposed pairing mechanism via two-particle hybridization can lead to $p$-superconducting states with $\eta$-pairing. $\eta$-pairing of spinless fermions could explain the phenomenon of high-temperature superconductivity experimentally observed in hydrogen-rich materials at high pressures.

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Igor N. Karnaukhov. 2026-04-23. $\eta$-pairing in a two-band model of spinless fermions. https://arxiv.org/abs/2604.21318

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