9:30 AM - 9:45 AM
▲ [16a-421-3] Optical force-assisted targeted deposition of molecular nanoparticles in the nanogap of a plasmonic nanoantenna
Keywords:optical trapping, plasmonics, molecular nanoparticle
Plasmonic nanoantennas with resonant nanogap have the ability to confine light in subwavelength volume. In a context of active research on nanotechnologies, this unique property has raised tremendous interest as it leads to enhanced light-matter interactions at the nanoscale. For instance, nanoantennas were recently used to designstate-of-the-artsingle-molecule sensors.This much localized light confinement also results in enhanced near-field optical forces,making it possible to trap single nanoparticles near or in the nanogap of plasmonic nano antennas. Over the past decade, plasmonic nanoantennas have been mainly used as plasmonic nanotweezers for reversible optical trapping, in other words, experiments consisting in successively trapping and then releasing nano-objects in suspension. We investigate here the still much unexplored field ofplasmonic trapping-assisted assembly of nanomaterials.In this work, nanoparticles exclusively made of fluorescent dye molecules were fabricated in water dispersion. Near-field optical forces arising from the resonant gap-mode of gold nanoantennas were then used to attract and deposit single nanoparticles in the vicinity of plasmonic nanogaps. Figure 1 shows a scanning electron microscope(SEM)image of a nanoparticle adsorbed in the gap of a trimer nanostructure.This one-step deposition process enables fast deposition ofsmall amount of matter directly from a colloidal suspension to a much localized location of interest. Therefore,this work is thought to pave the way for a wide range of further applications involving light-matter interactions at the nanoscale.