Photonic Flat Bands in Dielectric Metasurfaces

Abstract

Photonic flat bands allow for the realization of angle-insensitive, wavelength-selective resonances. By engineering the meta-atoms of a dielectric metasurface, a photonic band can be realized that is flat along one principal axis of momentum, and by additionally engineering the symmetry of the lattice, a locally flat photonic band can be realized in all directions around the gamma point of the Brillouin zone. Measurement of these devices with energy-momentum spectroscopy can be used to confirm their flat band dispersion. The one-dimensional flat band metasurface is used to demonstrate dispersion engineering of visible emitters. Potential applications for one- and two- dimensional photonic flat band metasurfaces are discussed.