Electrochemical tuning of the optical properties of nanoporous gold

Dirk Jalas, Li-Hua Shao, Rashmi Canchi, Toshiya Okuma, Slawa Lang, Alexander Petrov, Jörg Weißmüller & Manfred Eich
Using optical in-situ measurements in an electrochemical environment, we study the electrochemical tuning of the transmission spectrum of films from the nanoporous gold (NPG) based optical metamaterial, including the effect of the ligament size. The long wavelength part of the transmission spectrum around 800 nm can be reversibly tuned via the applied electrode potential. The NPG behaves as diluted metal with its transition from dielectric to metallic response shifted to longer wavelengths. We find that the...