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Polaron features for long-range electron-phonon interaction

C. A. Perroni·V. Cataudella·G. De Filippis
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Abstract

The polaron features for long-range electron-phonon interaction are investigated by extending a variational approach previously proposed for the study of systems with local coupling. The ground-state spectral weight, the average kinetic energy, the mean number of phonons, and the electron-lattice correlation function are discussed for a wide range of model parameters focusing on the adiabatic regime and comparing the results with the short-range case (Holstein model). A strong mixing of electronic and phononic degrees of freedom for small values of the electron-phonon coupling constant is found in the adiabatic case due to the long-range interaction. Finally a polaron "phase diagram" is proposed.

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C. A. Perroni, V. Cataudella, G. De Filippis. 2004-02-07. Polaron features for long-range electron-phonon interaction. https://doi.org/10.1088/0953-8984%2F16%2F9%2F007

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