The field-effect technique, popular thanks to its application in common field-effect transistors, is here applied to metallic thin films by using as a dielectric a novel polymer electrolyte solution. The maximum injected surface charge, determined by a suitable modification of a classic method of electrochemistry called double-step chronocoulometry, reached some units in 10^15 charges/cm^2. At room temperature, relative variations of resistance up to 8%, 1.9% and 1.6% were observed in the case of gold, silver and copper, respectively and, if the films are thick enough (> 25 nm), results can be nicely explained within a free-electron model with parallel resistive channels. The huge charge injections achieved make this particular field-effect technique very promising for a vast variety of materials such as unconventional superconductors, graphene and 2D-like materials.
@article{arxiv.1301.3769,
title = {Huge field-effect surface charge injection and conductance modulation in metallic thin films by electrochemical gating},
author = {M. Tortello and A. Sola and Kanudha Sharda and F. Paolucci and J. R. Nair and C. Gerbaldi and D. Daghero and R. S. Gonnelli},
journal= {arXiv preprint arXiv:1301.3769},
year = {2013}
}
Comments
6 pages, 6 figures. Applied Surface Science, in press