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arXiv · 1608.03514

Ab initio Electron Mobility and Polar Phonon Scattering in GaAs

Jin-Jian Zhou·Marco Bernardi
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Abstract

In polar semiconductors and oxides, the long-range nature of the electron-phonon (\textit{e}-ph) interaction is a bottleneck to compute charge transport from first principles. Here, we develop an efficient ab initio scheme to compute and converge the \textit{e}-ph relaxation times (RTs) and electron mobility in polar materials. We apply our approach to GaAs, where using the Boltzmann equation with state-dependent RTs, we compute mobilities in excellent agreement with experiment at 250$-$500~K. The $e$-ph RTs and the phonon contributions to intravalley and intervalley $e$-ph scattering are also analyzed. Our work enables efficient ab initio computations of transport and carrier dynamics in polar materials.

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Jin-Jian Zhou, Marco Bernardi. 2016-08-11. Ab initio Electron Mobility and Polar Phonon Scattering in GaAs. https://doi.org/10.1103/physrevb.94.201201

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