We present an exact ab initio theory for describing the motion of interacting electrons through nanoscopic constrictions. Our theory is based on time-dependent density functional theory (TDDFT) and nonequilibrium Green functions. We consider the system electrode-device-electrode initially contacted and in equilibrium, therefore the scheme is thermodynamically consistent. Besides the steady-state responses one can also calculate physical dynamical responses. We show that the steady-state current results from a dephasing mechanism provided the electrodes are macroscopic and the device is finite. In the d.c. case, we obtain a Landauer-like formula when the effective potential of TDDFT is uniform deep inside the electrodes.
|Journal||ournal of Physics Conference Series|
|Publication status||Published - 2006|
Subject classification (UKÄ)
- Condensed Matter Physics