First-principles time-dependent quantum transport theory

Abstract

A practical first-principles scheme for time-dependent transport through realistic systems at finite temperature is established by the combination of time-dependent density functional theory and nonequilibrium Green's-function formalism with wide-band limit approximation. This method extends the adiabatic wide-band limit approximation developed earlier [Zheng et al., Phys. Rev. B 75, 195127 (2007)]. It is implemented with both time-dependent density functional theory and time-dependent density functional tight-binding method and is applied to simulate the time-dependent transport through a carbon nanotube based electronic device to demonstrate its validity.