Multiband all-dielectric frequency selective surface filters for the mid-infrared

A DFSS filter comprised of a-Si blocks on a polyimide substrate was designed to have dual stopbands in the mid-IR. Full-wave simulation of this structure including measured material properties predicts strong polarization independent stopbands at 80 THz and 90 THz for normally incident IR radiation. This design was fabricated using e-beam lithography. Efforts are currently underway to characterize the fabricated structure and to generate additional DFSS designs using GA optimization.