Carbon‐Coated Moth‐Eye Structure: An Ultrabroadband THz‐DUV Near‐Perfect Absorber

Abstract A nearly perfect absorber across an ultrabroad frequency range from 1 to 1200 THz is reported that combines a silicon moth‐eye structure with a thin layer of pyrolytic carbon (PyC). The moth‐eye design provides a perfect impedance match with air via gradual change of the refractive index at low frequencies and simultaneously serves as a multiple scatterer at high frequencies while coating the moth‐eye structure with PyC enables ultrabroad band absorption. The combination of the strong absorption in the PyC conductive film and moth‐eye surface allows to create a material capable of absorbing over 98% incident radiation across the entire THz–deep ultraviolet (DUV) frequency range. This makes this moth‐eye/PyC structure a promising material for a wide range of applications including energy harvesting, electromagnetic shielding, and the development of an ideal blackbody radiation source.