Broad electrical tuning of plasmonic nanoantennas at visible frequencies

Abstract

We report an experimental demonstration of electrical tuning of plasmon resonances of optical nanopatch antennas over a wide wavelength range. The antennas consist of silver nanocubes separated from a gold film by a thin 8 nm polyelectrolyte spacer layer. By using ionic liquid and indium tin oxide coated glass as a top electrode, we demonstrate dynamic and reversible tuning of the plasmon resonance over 100 nm in the visible wavelength range using low applied voltages between −3.0 V and 2.8 V. The electrical potential is applied across the nanoscale gap causing changes in the gap thickness and dielectric environment which, in turn, modifies the plasmon resonance. The observed tuning range is greater than the full-width-at-half-maximum of the plasmon resonance, resulting in a tuning figure of merit of 1.05 and a tuning contrast greater than 50%. Our results provide an avenue to create active and reconfigurable integrated nanophotonic components for applications in optoelectronics and sensing.

Extreme nanophotonics from ultrathin metallic gaps

“…6a, ) and better colour tuning ( ). Due to the high local field enhancements in the gap, a small change in the properties of the material in this region, such as index of refraction or thickness, results in a large change in plasmon resonance, useful for real-time reconfigurable structures [105][106][107] or sensing 108 . In this way large area sub-μs colour changing wallpapers 109 (FIG.…”

Rectifying antennas for energy harvesting from the microwaves to visible light: A review

“…The size of the metallic planes as well as the distance that separates them are directly linked to the resonance wavelengths of the system, thus linked to the absorption wavelengths of the antenna array. Several designs exist : nanorods (figure 7a), which geometry is isotropic in one The dielectric thin film can be deposited using dip-coating methods [43] but self-assembly processes can also be implemented. Lin et al [42], for instance, have shown impressive assembly of controled nanoparticle assembly on metallic substrates as well as on other nanoparticle shapes, thanks to the complementarity of two DNA strands.…”

Active plasmonic nanoantenna: an emerging toolbox from photonics to neuroscience

“…A concerted and interdisciplinary effort has been devoted to the development of active systems in realization of postfabrication dynamic reconfigurability in a fully reversible and repeatable, fast, and ideally programmable manner. Until now, a variety of schemes have been proposed and developed in pursuit of in situ active control by electrical [153][154][155], chemical [156][157][158][159], optical [160], thermal [161], or mechanical [162][163][164] [165], tunable flat lenses [166], holograms [167], dynamic switches [66], interferometry photonic platforms [168], neural activity tracking [10,69], and information encryption [169]. Physical mechanisms behind these active plasmonic devices can be understood using lumped optical nanocircuit theory.…”