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Screening effects in the electron-optical phonon interaction

M. Reizer
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Abstract

We show that recently reported unusual hardening of optical phonons renormalized by the electron-phonon interaction is due to the neglect of screening effects. When the electron-ion interaction is properly screened optical phonons soften in three dimension. It is important that for short-wavelength optical phonons screening is static while for long-wavelength optical phonons screening is dynamic. In two-dimensional and one-dimensional cases due to crossing of the nonperturbed optical mode with gapless plasmons the spectrum of renormalized optical phonon-plasmon mode shows split momentum dependence.

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M. Reizer. 1999-07-02. Screening effects in the electron-optical phonon interaction. https://doi.org/10.1103/physrevb.61.40

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