Quantum transport properties of ultrathin silver nanowires

TL;DR

This study investigates the quantum transport properties of ultrathin silver nanowires, revealing how defects influence conductance channels and demonstrating the robustness of certain conduction pathways.

Contribution

It provides a detailed analysis of how atomic defects affect conductance channels in ultrathin silver nanowires, including quantum interference effects and statistical conductance behavior.

Findings

Three conduction channels in perfect nanowires crossing the Fermi level.

Single-atom defects disrupt one conductance channel.

Multiple-atom defects leave one conduction channel robust.

Abstract

The quantum transport properties of the ultrathin silver nanowires are investigated. For a perfect crystalline nanowire with four atoms per unit cell, three conduction channels are found, corresponding to three $s$ bands crossing the Fermi level. One conductance channel is disrupted by a single-atom defect, either adding or removing one atom. Quantum interference effect leads to oscillation of conductance versus the inter-defect distance. In the presence of multiple-atom defect, one conduction channel remains robust at Fermi level regardless the details of defect configuration. The histogram of conductance calculated for a finite nanowire (seven atoms per cross section) with a large number of random defect configurations agrees well with recent experiment.