High-temperature superconductivity from realistic Coulomb and Frohlich interactions by A.S. Alexandrov, John Samson, G. Sica

“…On this basis, we propose and study a model for high-Tc superconductivity which accounts for realistic Coulomb repulsion, strong electron-phonon (Frohlich) interaction and residual on-site (Hubbard ~U ) correlations without any ad-hoc assumptions on their relative strength and interaction range. …”
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Pseudogap in high-temperature superconductors from realistic Frohlich and Coulomb interactions by G. Sica, John Samson, A.S. Alexandrov

“…It has been recently shown that the competition between unscreened Coulomb and Frohlich electron-phonon interactions can be described in terms of a short-range spin exchange Jp and an effective on-site interaction ˜U in the framework of the polaronic t-Jp-˜U model. …”
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Electron-electron and electron-phonon interactions in strongly correlated systems by G. Sica

“…These findings, discussed in the framework of the so-called polaronic t-Jp model, are further investigated in the presence of a finite on-site potential U, coming from the competition between on-site Coulomb and Fröhlich interactions. …”
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Singlet and triplet bipolarons on the triangular lattice by J.P. Hague, P.E. Kornilovitch, John Samson, A.S. Alexandrov

“…We examine a simplified model of crab bipolarons with angular momentum by projecting onto the low energy subspace of the Coulomb–Fröhlich model with large phonon frequency. Such a projection is consistent with large long-range electron–phonon coupling and large repulsive Hubbard U. …”
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Strictly localised triplet dimers on one- and two-dimensional lattices by Steven Jackson, John Samson

“…For example, long-range (Fröhlich) electron-phonon interactions and strong on-site Hubbard U allow formation of small light bipolarons in some lattices. …”
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