Approach to steady state transport in nanoscale conductors

TL;DR

This paper demonstrates that a quasi-steady state current can be dynamically established in nanoscale conductors using a tight-binding model and density-functional theory, without inelastic effects, aligning with static scattering results.

Contribution

It introduces a method to observe steady state transport in finite nanoscale systems dynamically, highlighting the role of geometrical constriction and local electron distributions.

Findings

Quasi-steady state current can be achieved dynamically in finite systems.

Local electron occupation functions approach Fermi distributions.

Conductance and I-V characteristics match static scattering calculations.

Abstract

We show, using a tight-binding model and time-dependent density-functional theory, that a quasi-steady state current can be established dynamically in a finite nanoscale junction without any inelastic effects. This is simply due to the geometrical constriction experienced by the electron wavepackets as they propagate through the junction. We also show that in this closed non-equilibrium system two local electron occupation functions can be defined on each side of the nanojunction which approach Fermi distributions with increasing number of atoms in the electrodes. The resultant conductance and current-voltage characteristics at quasi-steady state are in agreement with those calculated within the static scattering approach.