Plasmonic resonances hosted by metallic nanostructures endow them to resonantly interact with light at nanometer scales. An alternative strategy to plasmonic materials consists of using high refractive index dielectric particles to manipulate light at the nanoscale. Silicon particles are of particular interest because they feature low order Mie resonances with electric and magnetic modes of similar magnitude. The interplay between electric and magnetic modes opens novel routes to design optical antennas with high gains in directivity or to tailor the electric and magnetic decay rates of quantum emitters. In this context, we quantified the Purcell factor of spherical silicon particles homogeneously doped with quantum emitters with the theory of quasi-normal modes. When coupled with chiral emitters, the coupling between electric and magnetic modes permits to tailor the chirality of light emission with achiral spherical dielectric particles. We will show that silicon nanogap antennas behave as suitable platforms to detect single fluorescent molecules freely diffusing in aqueous solution at micromolar concentration. Besides optical antennas, electric and magnetic Mie resonances hosted by silicon particles can also be used to print colored images with all-dielectric metasurfaces .


Seminar, April 18, 2017, 12:00. Seminar Room

Hosted by Prof. Romain Quidant / Prof. Javier García de Abajo