Counting Statistics of Parallel Al atomic wires

TL;DR

This study investigates how lateral interactions between parallel aluminum atomic wires influence their electrical conductance, shot noise, and skewness, revealing that close proximity enhances conductance and alters current fluctuations.

Contribution

The paper introduces a first-principles self-consistent approach using wave functions and the Lippmann-Schwinger equation to analyze multi-order current correlations in atomic wires.

Findings

Increased conductance when wires are close due to electron delocalization.

Generation of a side-band peak around maximum conductance.

Negative correlation between the third-order Fano factor and conductance.

Abstract

We have studied how the lateral interaction affects the electric conductance, the second-order current correlation (shot noise), and the third-order one (skewness) of a pair of parallel Al atomic wires. The field operator of wave function is introduced to calculate the current-current correlations. The corresponding wave functions are self-consistently obtained by iteration according to the Lippmann-Schwinger First-principles calculation. The results show that when the distance between two wires is sufficiently small, the bonding interaction near the Fermi level will induce a spatial delocalization of electrons. This leads to an electric conduction value greater than the sum of two uncorrelated atomic wire, and a side-band peak is generated around the maximum conductance. This correlation can also be observed from the shot noise and the skewness. In addition, we found that the three-order Fano factor is negatively related to the conductance.