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arXiv · 0807.3866

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

F. -Q. Xie·R. Maul·S. Brendelberger·Ch. Obermair·E. B. Starikov·W. Wenzel·G. Schoen·Th. Schimmel
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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.

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F. -Q. Xie, R. Maul, S. Brendelberger, Ch. Obermair, E. B. Starikov, W. Wenzel, G. Schoen, Th. Schimmel. 2008-07-24. Pre-selectable integer quantum conductance of electrochemically fabricated silver point contacts. https://doi.org/10.1063/1.2955521

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