Electrochemical Fine Tuning of the Plasmonic Properties of Au Lattice Structures

Abstract

We tuned the plasmonic properties of the Au lattice structure by electrochemical potential control. Au lattice structures with different values of the spacing, diameter, and height show characteristic optical properties determined by the surface lattice resonance of the localized surface plasmon mode. Electrochemical potential control can change the metal structures through metal dissolution, as well as the energy of the electrons in metals. In situ real time observation of the optical properties of Au lattice structures by electrochemical dark-field scattering microscopy shows the fine-tuning of the plasmonic properties with characteristic resonance energy and controlled spectral width. By controlling surface dissolution of the Au lattice structure at a rate of a few nanometers per minute, we tuned the plasmonic properties and achieved a spectral width of 0.145 eV at a maximum resonance of 1.74 eV (714 nm).

Recent Progress in Active Optical Metasurfaces

“…Particularly, chemical changes due to electrochemical reactions offer a unique approach for electrically controllable plasmonics that are sensitive to the chemical constituent and the surface carrier properties of the nanostructures. Electrochemical potential controlled plasmonic devices have recently been reported and should prove useful for active and fine tuning of plasmonic properties of metallic metasurfaces . Dramatic plasmonic resonance tuning based on surface‐charge density modulation was first observed in arrays consisting of 10 nm thick gold SRR and has been recently reidentified in gold nanoporous systems with remarkable surface‐to‐volume ratios .…”

“…Harnessing the Ag–AgCl redox chemical reaction, Byers et al have demonstrated a reversibly tunable resonance of silver‐based plasmonic nanoparticles . Similarly, by electrochemically controlling the structure of nanoantennas through metal dissolution, Minamimoto et al recently have reported fine tuning of the plasmonic behavior of gold nanodisk arrays . Wang et al have demonstrated real‐time color control of plasmonic metasurfaces based on the combination of bimetallic nanodot arrays and electrochemical bias .…”

Design for quality: reconfigurable flat optics based on active metasurfaces

“…Large wavelength shift of plasmonic antennas has been realized using this approach [220][221][222]. The second technique involves chemical changes of the meta-atoms instigated by electrochemical redox reactions in metals [223][224][225][226] or mobile ion intercalation in transition metal oxides [227]. Active metasurfaces with reversible and nonvolatile switching behavior have been materialized using this technique [227].…”

Electrochemically driven dynamic plasmonics

“…The behavior can be observed in nanoparticles, nanorods, nanodimers, and Au lattices. [91][92][93][94] The rate of electrodissolution can be adjusted (accelerated by laser excitations with hot holes, 95 inhibited with low concentrations of oxoanions 96 ). Under potential deposition (UPD) 97 technologies can also be applied for metal dissolution of Au dimer structures.…”