Localization lengths of ultrathin disordered gold and silver nanowires

TL;DR

This paper estimates the localization lengths in ultrathin disordered gold and silver nanowires, revealing strong localization effects and the impact of disorder and wire thickness on electrical transport properties.

Contribution

It provides new insights into how disorder and wire dimensions influence localization lengths in ultrathin metallic nanowires.

Findings

Localization lengths can be very small with slight disorder.

Impurities significantly reduce conductance.

Thicker wires have longer localization lengths.

Abstract

The localization lengths of ultrathin disordered Au and Ag nanowires are estimated by calculating the wire conductances as functions of wire lengths. We study Ag and Au monoatomic linear chains, and thicker Ag wires with very small cross sections. For the monoatomic chains we consider two types of disorder: bounded random fluctuations of the interatomic distances, and the presence of random substitutional impurities. The effect of impurity atoms on the nanowire conductance is much stronger. Our results show that electrical transport in ultrathin disordered wires may occur in the strong localization regime, and with relatively small amounts of disorder the localization lengths may be rather small. The localization length dependence on wire thickness is investigated for Ag nanowires with different impurity concentrations.