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arXiv · 2104.04895

FourPhonon: An extension module to ShengBTE for computing four-phonon scattering rates and thermal conductivity

Zherui Han·Xiaolong Yang·Wu Li·Tianli Feng·Xiulin Ruan
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Abstract

FourPhonon is a computational package that can calculate four-phonon scattering rates in crystals. It is built within ShengBTE framework, which is a well-recognized lattice thermal conductivity solver based on Boltzmann transport equation. An adaptive energy broadening scheme is implemented for the calculation of four-phonon scattering rates. In analogy with $thirdorder.py$ in ShengBTE, we also provide a separate python script, $Fourthorder.py$, to calculate fourth-order interatomic force-constants. The extension module preserves all the nice features of the well-recognized lattice thermal conductivity solver ShengBTE, including good parallelism and straightforward workflow. In this paper, we discuss the general theory, program design, and example calculations on Si, BAs and $\mathrm{LiCoO_2}$.

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Zherui Han, Xiaolong Yang, Wu Li, Tianli Feng, Xiulin Ruan. 2021-04-11. FourPhonon: An extension module to ShengBTE for computing four-phonon scattering rates and thermal conductivity. https://doi.org/10.1016/j.cpc.2021.108179

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