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arXiv · 0708.1407

Interplay between electron-phonon and Coulomb interactions in cuprates

O. Gunnarsson·O. Rösch
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Abstract

Evidence for strong electron-phonon coupling in high-Tc cuprates is reviewed, with emphasis on the electron and phonon spectral functions. Effects due to the interplay between the Coulomb and electron-phonon interactions are studied. For weakly doped cuprates, the phonon self-energy is strongly reduced due to correlation effects, while there is no corresponding strong reduction for the electron self-energy. Polaron formation is studied, focusing on effects of Coulomb interaction and antiferromagnetic correlations. It is argued that experimental indications of polaron formation in undoped cuprates are due to a strong electron-phonon interaction for these systems.

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O. Gunnarsson, O. Rösch. 2007-08-10. Interplay between electron-phonon and Coulomb interactions in cuprates. https://doi.org/10.1088/0953-8984%2F20%2F04%2F043201

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