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Phonon spectral function for an interacting electron-phonon system

J. E. Han·O. Gunnarsson
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Abstract

Using exact diagonalzation techniques, we study a model of interacting electrons and phonons. The spectral width of the phonons is found to be reduced as the Coulomb interaction U is increased. For a system with two modes per site, we find a transfer of coupling strength from the upper to the lower mode. This transfer is reduced as U is increased. These results give a qualitative explanation of differences between Raman and photoemission estimates of the electron-phonon coupling constants for A3C60 (A= K, Rb).

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J. E. Han, O. Gunnarsson. 1999-10-20. Phonon spectral function for an interacting electron-phonon system. https://doi.org/10.1103/physrevb.61.8628

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