Figure 3.

VO₂ metasurface modulator fabrication. (a) Schematic showing the fabrication pathway for a nanostructured VO₂ Huygens optical modulator. EBD (electron beam deposition), EBL (electron beam lithography), DEV (development), RIE (reactive ion etching), and IM (ion milling). (b). Scanning electron micrograph of ex situ annealed VO₂ thin film. (c). Anisotropically etched VO₂ nanodisks were fabricated using a SiO₂ hard mask layer to protect the VO₂ nanoantennas from being etched. This is advantageous because any leftover unetched SiO₂ mask does not alter the modulating performance of the metasurface once it is encapsulated in PDMS (Figure S-5).