posted on 2020-04-06, 19:04authored byDaniel Andrén, Jade Martínez-Llinàs, Philippe Tassin, Mikael Käll, Ruggero Verre
Phase-gradient
metasurfaces have the potential to revolutionize
photonics by offering ultrathin alternatives to a wide range of common
optical elements, including bulky refractive optics, waveplates, and
axicons. However, the fabrication of state-of-the-art metasurfaces
typically involves several expensive, time-consuming, and potentially
hazardous processing steps. To address this limitation, a facile methodology
to construct phase-gradient metasurfaces from an exposed standard
electron beam resist is developed. The method dramatically cuts the
required processing time and cost as well as reduces safety hazards.
The advantages of the method are demonstrated by constructing high-performance
flat optics based on the Pancharatnam-Berry phase gradient concept
for the entire visible wavelength range. Manufactured devices include
macroscopic (1 cm diameter) positive lenses, gratings exhibiting anomalous
reflection, and cylindrical metalenses on flexible plastic substrates.