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Phonon mediated hole pairing in the 1D Hubbard model near half-filling

Yury Petrov·Takeshi Egami
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Abstract

The Hamiltonian describing a system of strongly correlated electrons coupled to dispersionless phonons was solved numerically for a ring of 8 atoms using the density matrix renormalization group (DMRG) method. It was found that electron correlation and electron-phonon coupling compete against each other, and strong electron correlations suppress the charge-ordered insulating state. This allows extended polarons to form in the strong electron-phonon coupling regime. It is shown that in this regime two polarons may form a pair via phonon mediated charge-fluctuation interaction. Based on the results we propose a novel mechanism of hole pairing. This mechanism could be relevant to High-Tc cuprates.

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Yury Petrov, Takeshi Egami. 2000-04-20. Phonon mediated hole pairing in the 1D Hubbard model near half-filling. https://arxiv.org/abs/cond-mat/9912449

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