Electrochemical Control of Light Transmission through Nanohole Electrode Arrays

Control of the surface plasmon resonance (SPR) enhanced light transmission through array of nanoholes on gold films was achieved by modifying the metal surface with a thin layer of electroconductive polymer film. The electrochromic properties of the polymer were then triggered by tuning the electrochemical potential. Conducting polymer-modified nanohole array electrodes were prepared by electrodeposition of polypyrrole (PPy) using cyclic voltammetry. Only the gold surfaces inside the holes were accessible for film formation. The doping level of the PPy film was tuned by the electrochemical potential allowing fine control for the amount of light transmitted through the arrays. The concept demonstrated here paves the way for the fabrication of a new type of controllable nanometric optoelectronic devices based on polymeric materials.