Resonantly confining light in air: The dielectric Mie voids

Manipulating light at the nanoscale has become a central challenge in photonic metastructures, resonant metasurfaces, nanoscale optical sensors, and many more, and it is largely based on resonant light confinement in dispersive and lossy metals and dielectrics. We present the theoretical framework for resonantly confining light in air surrounded by high-index dielectrics and compare it with experiments. This confinement works down to the ultraviolet and can be understood to some extent via a generalization of the Babinet’s principle to dielectrics.