Dielectric nanoantennas

Common choice for the composition of nanoparticles for enhancing the interaction of light and molecules was until very recently limited to noble metals. Spectroscopic properties of gold, silver or palladium nanoparticles, nature of induced resonant modes and their interaction with the incident light, radiation of dipolar emitters and relativistic electrons are some of the topics of research conducted in our group.

Recently however, an interesting alternative to using the plasmonic nanoparticles has been discovered in high-refractive index nanospheres. Specifically, it has been shown that such nanoantennas exhibit tunable and spectrally separated electric and magnetic geometric modes. Furthermore, if – on top of having a high refractive index – loss-less materials are used, the interaction of such nanoantennas with fluorescent molecules is not limited at small separation distances by quenching of the fluorescence.

With those and other applications in mind, we investigate the interaction of electric and magnetic dipolar emitters with high-refractive index nanoantennas and spectroscopic properties of complex structures comprising such nanoparticles.