Conductance of atom-sized contacts of dilute Al alloys

Abstract

We have measured the conductance of atom-sized contacts of some dilute Al alloys in ultrahigh vacuum at room temperature. Measurements on Al-1.1at%Si, Al-2.8at%Mg, and Al-1.1at%Mg-0.6at%Si show no significant alloying effects: their conductance histograms are substantially the same as that of pure Al and exhibit a first peak corresponding to the single-atom contact of Al. On the other hand, a multicomponent Al alloy, Al-4.2at%Zn-3.6at%Mg-0.7at%Cu-0.01at%Ag (“meso10”), yields a conductance histogram which is totally different from others and shows no single-atom conductance peak of Al. We consider that in this high-strength alloy, the influence of alloying on the conductance would be mechanical rather than electronic. [DOI: 10.1380/ejssnt.2009.741]