Density of states and magnetoconductance of disordered Au point contacts

Abstract

We report the first low temperature magnetotransport measurements on electrochemically fabricated atomic scale gold nanojunctions. As $T\to 0$, the junctions exhibit nonperturbatively large zero bias anomalies (ZBAs) in their differential conductance. We consider several explanations and find that the ZBAs are consistent with a reduced local density of states (LDOS) in the disordered metal. We suggest that this is a result of Coulomb interactions in a granular metal with moderate intergrain coupling. Magnetoconductance of atomic scale junctions also differs significantly from that of less geometrically constrained devices, and supports this explanation.

arXiv comment5 pages, 5 figures. Accepted to PRB as Brief Report

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Cited by in corpus (5)

• Formation of Atomic-Sized Contacts by Electrochemical Methods
• Localization and Capacitance Fluctuations in Disordered Au Nano-junctions
• Normal State Gap in Parent Cuprate Pr2CuO4+/-δ
• Critical behavior of density of states near Fermi energy in low-dimensional disordered metals
• Spin-Based Magnetofingerprints and Dephasing in Strongly Disordered Au-Nanobridges