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Signatures of band-like tunnelling in granular nanowires

J. Fransson·J. -F. Lin·L. Rotkina·J. P. Bird·P. A. Bennett
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Abstract

We explore the problem of tunneling through disorderd nanowires, comprised of a random distribution of metallic grains, by means of a many-body model that captures the essential physics of the system. The random configuration of grains gives rise to a smooth band-like set of states, which mediates current flow through the nanowire. Analytical and numerical calculations show the characteristic signature of this unusual band-like transport to be a quadratic variation of the current as a function of the applied voltage (i.e. $I\sim V^2$), a variation that is clearly observed in experimental studies of Pt/C composite nanowires.

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J. Fransson, J. -F. Lin, L. Rotkina, J. P. Bird, P. A. Bennett. 2005-02-18. Signatures of band-like tunnelling in granular nanowires. https://doi.org/10.1103/physrevb.72.113411

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