Four-atom period in the conductance of monatomic Al wires

TL;DR

This paper uses first principles calculations to reveal a unique four-atom periodic oscillation in the conductance of monatomic aluminum wires, differing from typical even-odd oscillations, explained via a resonant transport model.

Contribution

It introduces a novel four-atom conductance oscillation in monatomic Al wires and explains it with a resonant transport model based on electronic structure.

Findings

Conductance oscillates with a period of 4 atoms in Al wires.

Local charge neutrality explains the period but not the phase.

Resonant transport model accounts for the conductance behavior.

Abstract

We present first principles calculations based on density functional theory for the conductance of monatomic Al wires between Al(111) electrodes. In contrast to the even-odd oscillations observed in other metallic wires, the conductance of the Al wires is found to oscillate with a period of 4 atoms as the length of the wire is varied. Although local charge neutrality can account for the observed period it leads to an incorrect phase. We explain the conductance behavior using a resonant transport model based on the electronic structure of the infinite wire.