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arXiv · 1108.3099

Large conductance modulation of gold thin films by huge charge injection via electrochemical gating

D. Daghero·F. Paolucci·A. Sola·M. Tortello·G. A. Ummarino·R. S. Gonnelli·Jijeesh R. Nair·C. Gerbaldi
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Abstract

By using an electrochemical gating technique with a new combination of polymer and electrolyte, we were able to inject surface charge densities n_2D as high as 3.5 \times 10^15 e/cm^2 in gold films and to observe large relative variations in the film resistance, DeltaR/R', up to 10% at low temperature. DeltaR/R' is a linear function of n_2D - as expected within a free-electron model - if the film is thick enough (> 25 nm), otherwise a tendency to saturation due to size effects is observed. The application of this technique to 2D materials will allow extending the field-effect experiments to a range of charge doping where giant conductance modulations and, in some cases, even the occurrence of superconductivity are expected.

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D. Daghero, F. Paolucci, A. Sola, M. Tortello, G. A. Ummarino, R. S. Gonnelli, Jijeesh R. Nair, C. Gerbaldi. 2011-08-15. Large conductance modulation of gold thin films by huge charge injection via electrochemical gating. https://doi.org/10.1103/physrevlett.108.066807

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