ABSTRACT
In this study, we investigated an absorber based on a center-aligned tandem nanopillar array for ultra-broadband solar energy harvesting theoretically. A high-efficiency, omnidirectional absorber was obtained by introducing the center-aligned tandem nanopillar array embedded in an Al2O3 dielectric layer. The multi-coupling modes at different wavelengths were interpreted. The strong absorption can be adjusted by changing the radii and heights of nanopillars. According to the simulation results, the average absorptance of the absorber exceeded 94% in the wavelength range from 300 nm to 2000 nm. In addition, the high-efficiency absorption was insensitive to the incident angle and polarization state. The research not only proposed an absorber which possesses a huge potential value for application areas, such as thermal photovoltaic systems, infrared detection, and isotropic absorption sensors, but also pointed out a new way to design an absorber with high efficiency in an ultrabroad wavelength range.
ABSTRACT
Titanium nitride (TiN) is a metal-like refractory material that can be used as a substitution for metals in many applications. In this paper, we report the use of an ultra-thin TiN film in the Salisbury screen structure to spectral selectively absorb visible light for forming an optical color filter. The ultra-thin TiN film functions as a partial reflector as well as a protection capping layer in the structure. Spectral selective perfect absorption color filters with TiN-ZnO-Al multilayer films were fabricated and characterized.
