Pre-selectable integer quantum conductance of electrochemically fabricated silver point contacts

TL;DR

This paper presents a method combining electrochemical deposition and annealing to fabricate silver atomic contacts with pre-selected integer quantum conductance, improving control over contact properties.

Contribution

It introduces a novel fabrication technique enabling the creation of atomic-scale silver contacts with predetermined conductance values, verified by conductance measurements and theoretical modeling.

Findings

Successful fabrication of silver point contacts with integer quantum conductance

Conductance measurements align with theoretical models of idealized geometries

Method allows for controlled and reproducible atomic-scale contact production

Abstract

The controlled fabrication of well-ordered atomic-scale metallic contacts is of great interest: it is expected that the experimentally observed high percentage of point contacts with a conductance at non-integer multiples of the conductance quantum G_0 = 2e^2/h in simple metals is correlated to defects resulting from the fabrication process. Here we demonstrate a combined electrochemical deposition and annealing method which allows the controlled fabrication of point contacts with pre-selectable integer quantum conductance. The resulting conductance measurements on silver point contacts are compared with tight-binding-like conductance calculations of modeled idealized junction geometries between two silver crystals with a predefined number of contact atoms.