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arXiv · 1103.3739

Public exhibit for demonstrating the quantum of electrical conductance

E. H. Huisman·F. L. Bakker·J. P. van der Pal·R. M. de Jonge·C. H. van der Wal
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Abstract

We present a new robust setup that explains and demonstrates the quantum of electrical conductance for a general audience and which is continuously available in a public space. The setup allows users to manually thin a gold wire of several atoms in diameter while monitoring its conductance in real time. During the experiment, a characteristic step-like conductance decrease due to rearrangements of atoms in the cross-section of the wire is observed. Just before the wire breaks, a contact consisting of a single atom with a characteristic conductance close to the quantum of conductance can be maintained up to several seconds. The setup is operated full-time, needs practically no maintenance and is used on different educational levels.

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E. H. Huisman, F. L. Bakker, J. P. van der Pal, R. M. de Jonge, C. H. van der Wal. 2011-03-19. Public exhibit for demonstrating the quantum of electrical conductance. https://doi.org/10.1119/1.3593276

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