All-dielectric, visible wavelength focusing metalens with planar surface for mechanical robustness

We present a path to truly ‘flat’, all-oxide metalenses working at visible wavelength comprising high-aspect ratio TiO
2
nanopillars infused into fused silica substrate. We show both a proof-of-concept infused metalens using electron-beam lithography, and an example of mass-manufacturing using deep-ultraviolet projection lithography.