Electric tuning and switching of the resonant response of nanoparticle arrays with liquid crystals

We report on the design, fabrication, and analysis of a tunable device combining nanoparticle arrays that support collective surface lattice resonances (SLRs) with liquid crystals (LCs). The optoelectronic tunability of the nematic LC and the dependency of sharp SLRs on the refractive index of the environment are exploited to achieve spectral tunability. This tunability is electrically controlled by switching between planar and homeotropic states in the LC, which allows for a rapid and reversible tuning of the SLR wavelength with a large degree of control. This device also offers the possibility to switch on and off the presence of a quasi-guided mode in the indium tin oxide electrode. The manipulation of these resonances with an external parameter can be used to expand the functionalities of plasmonic metasurface devices. (c) 2022 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(http://creativecommons.org/licenses/by/4.0/).

Automated summary

We report on the design, fabrication, and analysis of a tunable device combining nanoparticle arrays that support collective surface lattice resonances (SLRs) with liquid crystals (LCs). The optoelectronic tunability of the nematic LC and the dependency of sharp SLRs on the refractive index of the environment are exploited to achieve spectral tunability. This device offers rapid and reversible tuning of the SLR wavelength through electrical control of the LC state, and also enables control of the presence of a quasi-guided mode.