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arXiv · 2201.11912

High-field transport and hot electron noise in GaAs from first principles: role of two-phonon scattering

Peishi S. Cheng·Jiace Sun·Shi-Ning Sun·Alexander Y. Choi·Austin J. Minnich
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Abstract

High-field charge transport in semiconductors is of fundamental interest and practical importance. While the \textit{ab initio} treatment of low-field transport is well-developed, the treatment of high-field transport is much less so, particularly for multi-phonon processes that are reported to be relevant in GaAs. Here, we report a calculation of the high-field transport properties and current power spectral density (PSD) of hot electrons in GaAs from first principles including on-shell two-phonon (2ph) scattering. The on-shell 2ph scattering rates are found to qualitatively alter the high-field distribution function by increasing both the momentum and energy relaxation rates as well as contributing markedly to intervalley scattering. This finding reconciles a long-standing discrepancy regarding the strength of intervalley scattering in GaAs as inferred from transport and optical studies. The characteristic non-monotonic trend of PSD with electric field is not predicted at this level of theory. Our work shows how \textit{ab initio} calculations of high-field transport and noise may be used as a stringent test of the electron-phonon interaction in semiconductors.

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Peishi S. Cheng, Jiace Sun, Shi-Ning Sun, Alexander Y. Choi, Austin J. Minnich. 2022-07-06. High-field transport and hot electron noise in GaAs from first principles: role of two-phonon scattering. https://doi.org/10.1103/physrevb.106.245201

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