Conductance fluctuations as a tool for investigating the quantum modes in atomic size metallic contacts

TL;DR

This paper explores how conductance fluctuations in atomic-sized metallic contacts reveal information about quantum mode composition, extending experiments across various metals to understand conductance quantization and mode behavior.

Contribution

It introduces a broader experimental investigation of conductance fluctuations across different metals, linking mode composition to conductance quantization phenomena.

Findings

Conductance fluctuations are suppressed at integer multiples of the conductance quantum.

Contacts tend to have fully open or closed modes, influencing conductance histograms.

The relation between mode composition and preferred conductance values is clarified.

Abstract

Recently it has been observed that the conductance fluctuations of atomic size gold contacts are suppressed when the conductance is equal to an integer multiple of the conductance quantum. The fact that these contacts tend to consist exclusively of fully open or closed modes has been argued to be the origin for this suppression. Here, the experiments have been extended to a wide range of metallic elements with different chemical valence and they provide new information about the relation between the mode composition and statistically preferred conductance values observed in conductance histograms.