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Density of states and magnetoconductance of disordered Au point contacts

L. H. Yu·D. Natelson
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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.

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L. H. Yu, D. Natelson. 2003-07-23. Density of states and magnetoconductance of disordered Au point contacts. https://doi.org/10.1103/physrevb.68.113407

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