Ab Initio Dipolar Electron-Phonon Interactions In Two-Dimensional Materials

We develop an ab initio formalism for dipolar electron-phonon interactions (EPIs) in two-dimensional (2D) materials. Unlike the purely longitudinal Frohlich model, we show that the out-of-plane dipoles also contribute to the long-wavelength nonanalytical behavior of EPIs. And the 2D dipolar EPI plays an important role not only in the typical polar material MoS2, 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 the Frohlich model is inadequate for 2D materials and a correct long-wavelength interaction must be included for a reliable prediction.