Peak shift near-infrared metamaterial absorber with VO2 phase transition grating layer

A tunable peak shift narrow band metamaterial perfect absorber (MPA) with a high fill factor VO₂ phase transition grating layer operating at near-infrared waveband is studied theoretically and experimentally. The theoretical absorption peaks of the proposed MPA are located at 1080 nm (at 20 °C) and 946 nm (at 80 °C) respectively for normal incidence. The theoretical results show that the absorption spectra of the MPA are insensitive to the incident angles. The MPA exhibits a slight blue shift with the increase of surrounding media refractive index. Finally, the theoretical results are verified by the MPA sample fabrication and spectral measurements. The novel MPA can be better applied in microbolometers, pixel imaging, biochemical sensing and absorption filter et al.