Electron-phonon scattering in cold-metal contacted two-dimensional semiconductor devices

Using our DFT + NEGF code, we confirm previous work which shows that cold metal contacted transistors based on 2D materials can achieve subthreshold swings lower than the thermionic limit. This is, however, only true in the ballistic limit and is negated by scattering effects. Additionally, symmetrically connected devices suffer from degraded on-current which increases with increased source-drain bias due to reduced overlap of the energy windows of available states at source and drain.