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Apparent electron-phonon interaction in strongly correlated systems

O. Rösch·O. Gunnarsson
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Abstract

We study the interaction of electrons with phonons in strongly correlated solids, having high-T_c cuprates in mind. Using sum-rules, we show that the apparent strength of this interaction strongly depends on the property studied. If the solid has a small fraction (doping) delta of charge carriers, the influence of the interaction on the phonon self-energy is reduced by a factor delta, while there is no corresponding reduction of the coupling seen in the electron self-energy. This supports the interpretation of recent photoemission experiments, assuming a strong coupling to phonons.

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O. Rösch, O. Gunnarsson. 2004-07-02. Apparent electron-phonon interaction in strongly correlated systems. https://doi.org/10.1103/physrevlett.93.237001

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