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arXiv · 2002.00628

Electron-Phonon Beyond Fröhlich: Dynamical Quadrupoles in Polar and Covalent Solids

Guillaume Brunin·Henrique Pereira Coutada Miranda·Matteo Giantomassi·Miquel Royo·Massimiliano Stengel·Matthieu J. Verstraete·Xavier Gonze·Gian-Marco Rignanese·Geoffroy Hautier
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Abstract

We include the treatment of quadrupolar fields beyond the Fröhlich interaction in the first-principles electron-phonon vertex in semiconductors. Such quadrupolar fields induce long-range interactions that have to be taken into account for accurate physical results. We apply our formalism to Si (nonpolar), GaAs, and GaP (polar) and demonstrate that electron mobilities show large errors if dynamical quadrupoles are not properly treated.

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Guillaume Brunin, Henrique Pereira Coutada Miranda, Matteo Giantomassi, Miquel Royo, Massimiliano Stengel, Matthieu J. Verstraete, Xavier Gonze, Gian-Marco Rignanese, Geoffroy Hautier. 2020-09-21. Electron-Phonon Beyond Fröhlich: Dynamical Quadrupoles in Polar and Covalent Solids. https://doi.org/10.1103/physrevlett.125.136601

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