Electron-Phonon Scattering in Low-Dimensional Field Effect Transistors from First-principles*

Electron-phonon (e-p) scattering is an important effect for nonequilibrium quantum transport physics of electronic devices such as semiconductor field effect transistors. E-p scattering is often neglected, however, in atomistic device simulations due to the very large computational burden. To this end, an approximate but computationally efficient technique to include e-p scattering in electronic structure theory is the single-supercell approach (ZG method) where a supercell containing specially constructed atomic positions is simulated once, without explicitly calculating the e-p self-energy. This technique has also been applied to atomistic transport simulations. In this work, we apply the ZG method to investigate e-p scattering effects in FET structures made of low-dimensional materials, calculating the subthreshold swing of FETs for which the injecting source is a Dirac material.