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Evidence for saturation of channel transmission from conductance fluctuations in atomic-size point contacts

B. Ludoph·M. H. Devoret·D. Esteve·C. Urbina·J. M. van Ruitenbeek
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Abstract

The conductance of atomic size contacts has a small, random, voltage dependent component analogous to conductance fluctuations observed in diffusive wires (UCF). A new effect is observed in gold contacts, consisting of a marked suppression of these fluctuations when the conductance of the contact is close to integer multiples of the conductance quantum. Using a model based on the Landauer-Buettiker formalism we interpret this effect as evidence that the conductance tends to be built up from fully transmitted (i.e., saturated) channels plus a single, which is partially transmitted.

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B. Ludoph, M. H. Devoret, D. Esteve, C. Urbina, J. M. van Ruitenbeek. 1999-07-19. Evidence for saturation of channel transmission from conductance fluctuations in atomic-size point contacts. https://doi.org/10.1103/physrevlett.82.1530

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