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arXiv · 0809.4841

Scaling of 1/f noise in tunable break-junctions

ZhengMing Wu·SongMei Wu·S. Oberholzer·M. Steinacher·M. Calame·C. Schönenberger
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Abstract

We have studied the $1/f$ voltage noise of gold nano-contacts in electromigrated and mechanically controlled break-junctions having resistance values $R$ that can be tuned from 10 $Ω$ (many channels) to 10 k$Ω$ (single atom contact). The noise is caused by resistance fluctuations as evidenced by the $S_V\propto V^2$ dependence of the power spectral density $S_V$ on the applied DC voltage $V$. As a function of $R$ the normalized noise $S_V/V^2$ shows a pronounced cross-over from $\propto R^3$ for low-ohmic junctions to $\propto R^{1.5}$ for high-ohmic ones. The measured powers of 3 and 1.5 are in agreement with $1/f$-noise generated in the bulk and reflect the transition from diffusive to ballistic transport.

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ZhengMing Wu, SongMei Wu, S. Oberholzer, M. Steinacher, M. Calame, C. Schönenberger. 2008-09-28. Scaling of 1/f noise in tunable break-junctions. https://doi.org/10.1103/physrevb.78.235421

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