High-temperature ultra-broad UV–MIR high-efficiency absorber based on double ring-shaped titanium nitride resonators

An ultrabroad absorber based on double-ring-shaped titanium nitride (TiN) nanoresonators, which can work in high temperatures, is proposed and numerically studied. The with some optimal parameters exhibits an averaged absorption of 94.6% the range 200 - 4000 nm (from ultraviolet to mid-infrared) a band from 3518 having > 90%. We have demonstrated detail physical mechanisms ultra-broad absorption, including dielectric lossy property TiN material itself shorter wavelengths plasmonic resonances caused by metallic nano-resonators longer wavelengths. In addition, shows polarization independent wide-angle acceptance. Another double nano-rings different heights has flatter higher efficiency (more than 95% absorption) at 200-2860 waveband. These properties make absorbers great potentials many applications, such as light trapping, photovoltaics, thermal emitters.