Amplitude, phase, and polarization are the fundamental properties of light. Traditionally, controlling each property requires different kinds of conventional optical elements such as lenses, polarizers, or waveplates, which are bulky and heavy. Metasurfaces, which are ultrathin planar arrays of nanostructures, are revolutionizing these fields. Because of their capability to simultaneously control various properties of light such as amplitude, phase, and polarization with subwavelength resolution, they are replacing conventional optics but also realizing optical devices with unprecedented functionalities.
Recently, we demonstrated that dielectric metasurfaces with bi-layer structures, which we call universal metasurfaces, can support complete linear light control. Based on this demonstration, our current goal is to enlarge the applicability of universal metasurfaces to various scientific and engineering problems such as holograms, AR/VR, particle manipulation, or computational imaging.