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arXiv · 1509.05800

Electron-phonon-averaged approximation for first-principles computations of electron relaxation times and transport properties in semiconductor materials

Georgy Samsonidze·Boris Kozinsky
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Abstract

We present a simple and efficient approximation to the electron-phonon scattering rate suitable for high-throughput screening of candidate materials for thermoelectric devices, based on electronic transport. The method is applied to calculate the electronic transport coefficients of half-Heusler compounds, showing agreement with experimental data. By directly computing electrical and the electronic part of the thermal conductivities, we find deviations from the Wiedemann-Franz law in these compounds at high temperatures and low carrier concentrations.

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Georgy Samsonidze, Boris Kozinsky. 2015-09-18. Electron-phonon-averaged approximation for first-principles computations of electron relaxation times and transport properties in semiconductor materials. https://arxiv.org/abs/1509.05800

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