Glass-engraved metasurfaces: the path to ultra-low reflectance, extreme broadband performance, and high acceptance angle for high power laser applications

Recent work utilizing metal etching masks to fabricate substrate-engraved metasurfaces have been handicapped by the available etching depth, restricting the bandwidth of antireflective performance. Advances made to etch mask technology to facilitate deeper etching will be discussed here, and the taller ensuant metasurface features will be presented. The antireflective performance of these high aspect ratio structures (broad acceptance angles and broadband antireflective performance for both polarizations) will be discussed.