Arrays of metallic nanoparticles can type an optical cavity tunable by liquid crystals

The manuscript “Electrical tuning and switching of the resonant response of nanoparticle arrays with liquid crystals” by Erik van Heijst and associates (PSN) has been chosen as featured article and journal cowl within the final problem of the Journal of Utilized Physics and a SciLight article has been written by the American Institute of Physics. On this article, it’s proven how collective plasmonic resonances could be electrically managed with liquid crystals. That is the primary manuscript of the EHCI and ICMS collectively. Erik van Heijst did his work as a part of his commencement analysis within the Utilized Physics and Chemical Engineering division the place he obtained the double diploma final 12 months.

Plasmonic resonances in metallic nanoparticles have proven promise for a variety of purposes, together with nanolasers and very delicate nano-sized biosensors. The sector of plasmonics has seen regular enhancements towards energetic management over resonances utilizing the refractive index of the fabric between nanoparticles.

Van Heijst et al. designed, constructed and analyzed a tunable system combining nano-particle arrays that help collective floor lattice resonances (SLRs) with liquid crystals. By leveraging the tunability of liquid crystals and the impact of the refractive index of the surroundings on SLRs, the optical response of the array could be managed electrically by switching between states within the liquid crystal. The ensuing fast and reversible spectral tuning offers customers a big diploma of management over SLR wavelength.

Slim collective resonances inside arrays are key options within the system’s capability to tune resonance with such management.

“As a result of we have now slim collective resonances, then the modifications in refractive index that we will induce with the liquid crystal are ample to shift the resonance virtually its full width,” mentioned writer Jaime Gómez Rivas.

Regardless of being delocalized with respect to the person nanoparticles, the hybrid plasmonic-photonic modes of SLRs exhibit giant enhancements of the electrical subject depth.

Experimentally, the group discovered the SLR power shift was lower than what was indicated in simulations, which they attribute to the tough floor of the indium tin oxide electrodes and the imperfect alignment of liquid crystals imposed by the nanoparticle construction.

The group goals to tune the emission of molecules dispersed within the liquid crystal, which may then be coupled to the collective resonance and finally enable a change in crystal orientation.