Conduction Channels of One-Atom Zinc Contacts

TL;DR

This paper investigates the conduction channels in atomic-scale zinc contacts, revealing a dominant single channel in the last conductance plateau and explaining it via a tight-binding model involving 4s and 4p orbitals.

Contribution

It introduces a new breakjunction technique and provides the first detailed analysis of conduction channels in one-atom zinc contacts.

Findings

Transport is dominated by a single well-transmitting channel.

Current flows through 4s and 4p orbitals of the central atom.

Experimental results are supported by a tight-binding model.

Abstract

We have determined the transmission coefficients of atomic-sized Zn contacts using a new type of breakjunction which contains a whisker as a central bridge. We find that in the last conductance plateau the transport is unexpectedly dominated by a well-transmitting single conduction channel. We explain the experimental findings with the help of a tight-binding model which shows that in an one-atom Zn contact the current proceeds through the 4s and 4p orbitals of the central atom.