Lundgaard, S.; Ng, S.H.; Nishijima, Y.; Mazilu, M.; Juodkazis, S. Black Metals: Optical Absorbers. Micromachines2020, 11, 256.
Lundgaard, S.; Ng, S.H.; Nishijima, Y.; Mazilu, M.; Juodkazis, S. Black Metals: Optical Absorbers. Micromachines 2020, 11, 256.
Abstract
We demonstrate a concept and fabrication of lithography-free layered metal-\ce{SiO2} thin-film structures which have reduced reflectivity (black appearance), to as low as 0.9~\%, with 4.9~\% broadband reflectance (8.9~\% for soda lime) in the 500 - 1400~nm range. The multi-layered (four layers) thin-film metamaterial is designed so that optical impedance matching produces minimal reflectance and transmittance within the visible and infra-red (IR) spectral region for a range of incident angles. The structure has enhanced absorbance and is easily tuned for reduced minimal transmission and reflection.
Keywords
metalmaterial; optical absorber; thin-film optics
Subject
PHYSICAL SCIENCES, Optics
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.