11:15 AM - 11:30 AM
▲ [14a-2C-7] Chiral plate perfect absorber metamaterial for infra-red spectral range based on 3D spiral architecture
Keywords:optical metamaterial,perfect absorber,direct laser write
We report design, fabrication and optical haracteristics of chiral plate perfect absorber for infra-red (IR) spectral range based on metallic helices. The absorber architecture uses periodic arrangement of single-turn gold spirals on a metallic plane, and exhibits o resonant electromagnetic coupling leading and nearly perfect extinction of an incident plane wave within a single sub-wavelength thick spiral layer. The structures were designed and optimized using finite-element electromagnetic simulation, while their fabrication was carried out using direct laser write technique in a dielectric photoresist with subsequent metallization of the obtained dielectric template by gold sputtering. The fabricated absorber metamaterial was characterized using infra-red reflection spectroscopy, and was found do exhibit a resonant absorption band centered near the 7.6µm wavelength, with peak absorptivity reaching 90%, in accordance to the theoretical predictions. In the future, similar metallic perfect absorber metamaterials may be applied for enhancement of IR radiation harvesting, thermal detection, and electromagnetic energy conversion efficiency.