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arXiv · 1704.01690

Evolution of shot noise in suspended lithographic gold break junctions with bias and temperature

Ruoyu Chen·Douglas Natelson
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Abstract

Shot noise is a powerful tool to probe correlations and microscopic transport details that conductance measurements alone cannot reveal. Even in atomic-scale Au devices that are well described by Landauer-B{ü}ttiker physics, complications remain such as local heating and electron-phonon interactions. We report systematic rf measurements of shot noise in individual atomic-scale gold break junctions at multiple temperatures, with most bias voltages well above the energy of the Au optical phonon mode. Motivated by the previous experimental evidence that electron-phonon interactions can modify Fano factors and result in kinked features in bias dependence of shot noise, we find that the temperature dependence of shot noise from 4.2~K to 100~K is minimal. Enhanced Fano factors near 0.5$~G_0$ and features beyond simply linear bias dependence of shot noise near the 1$~G_0$ plateau are observed. Both are believed to have non-interacting origins and the latter likely results from slightly bias-dependent transmittance of the dominant quantum channel.

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Ruoyu Chen, Douglas Natelson. 2017-04-06. Evolution of shot noise in suspended lithographic gold break junctions with bias and temperature. https://doi.org/10.1088/0957-4484%2F27%2F24%2F245201

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