Quasi-ballistic electron transport in atomic wires

This article describes quasi-ballistic electron transport in atomic wires. It begins with a review of experiments on the conduction properties for single metal atoms. Nearly all the information on the properties of such nanocontacts should be extracted from the current and voltage only. Nevertheless, a wide range of techniques has been developed to obtain detailed information. The article proceeds by considering various experimental techniques for characterizing single-atom contacts, along with their application for the study of conducting chains of individual metal atoms and for metal–molecule–metal junctions. Using metallic point contacts and molecular junctions that are of atomic size, it demonstrates that the transport of electrons can be quasi-ballistic and the deviations from perfect transmission can be quantified and interpreted.