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arXiv · 2010.02437

Ab initio dipolar electron-phonon interactions in two-dimensional materials

Tianqi Deng·Gang Wu·Wen Shi·Zicong Marvin Wong·Jian-Sheng Wang·Shuo-Wang Yang
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Abstract

We develop an ab initio formalism for dipolar electron-phonon interactions (EPI) in two-dimensional (2D) materials. Unlike purely longitudinal Fröhlich model, we show that the out-of-plane dipoles also contribute to the long-wavelength non-analytical behavior of EPI. And the 2D dipolar EPI plays an important role not only in the typical polar material MoS$_2$, but also in graphane and fluorinated graphene. By incorporating this formalism into Wannier-Fourier interpolation, we enable accurate EPI calculations for 2D materials and subsequent intrinsic carrier mobility prediction. The results show that Fröhlich model is inadequate for 2D materials and correct long-wavelength interaction must be included for the reliable prediction.

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Tianqi Deng, Gang Wu, Wen Shi, Zicong Marvin Wong, Jian-Sheng Wang, Shuo-Wang Yang. 2020-12-30. Ab initio dipolar electron-phonon interactions in two-dimensional materials. https://doi.org/10.1103/physrevb.103.075410

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