Resonant nanophotonics with dielectric nanoparticles
Nanoscale optics is usually associated with plasmonic structures made of metals such as gold or silver. However, plasmonics suffers from high losses of metals, heating, and incompatibility with CMOS fabrication processes. Recent developments in the nanoscale optical physics has led to a new branch of nanophotonics aiming at the manipulation of optically induced Mie resonances in dielectric and semiconductor nanoparticles with high refractive index. Such particles offer unique opportunities for reduced dissipative losses and large resonant enhancement of both electric and magnetic near fields. Semiconductor nanostructures also offer longer excited-carrier lifetimes and can be electrically doped and gated to realize subwavelength active devices. These recent developments revolve closely around the nature of the optical resonances of the structures and how they can be manipulated in individual entities as well as complex particle arrangements such as metasurfaces. Resonant high-index dielectric nanostructures form new building blocks to realize unique functionalities and novel photonic devices.