First-principles mobilities with hybrid and Koopmans functionals

Electron-phonon interactions are crucial to understanding many properties of materials, such as electron and hole mobilities [1]. Accurate modelling of these interactions [2] can lead to innovative applications, going from efficient electronic devices to novel superconducting materials. However, the limitations of traditional DFT in predicting the electronic structure and charged excitations/band structures make it compelling to explore more accurate approaches, such as hybrid or Koopmans functionals [3]. This work focuses on the development of a general framework for calculating electron-phonon matrix elements on a coarse grid with beyond-DFT functionals, requiring only the eigenvalues and eigenfunctions of the relevant Hamiltonians. Performing later Wannier-Fourier interpolation to the dense grid allows us to study transport properties using the Boltzmann transport equation. We demonstrated our approach using hybrid or Koopmans functionals as case studies, showing the effect of these methods on electron-phonon couplings and mobilities for common semiconductors.

[1] S. Poncé, F. Macheda, E. Margine, N. Marzari, N. Bonini and F. Giustino, Phys. Rev. Research 3, 043022 (2021)

[2] F. Giustino, Rev. Mod. Phys. 89, 015003 (2017)

[3] N. Colonna, R. De Gennaro, E. Linscott, and N. Marzari, JCTC 18, 5435 (2022)