Conductive metal-oxide-based tunable, wideband, and wide-angle metamaterial absorbers operating in the near-infrared and short-wavelength infrared regions.

This paper investigates the absorption features of the gallium-doped zinc oxide (GZO) nanowire-based metamaterial absorber. The absorption spectrum was analyzed in the near-infrared regime (NIR) and short-wavelength infrared regime (SWIR). The wideband absorption was observed in the NIR and SWIR. The effect of the volume fraction of the nanorod and thickness of the metamaterial was depicted on the absorption spectrum. Observations reveal that at a lower volume fraction of GZO, absorption is noticed at SWIR of the spectrum; however, for a large volume fraction, blueshift in the absorption band is noticed, and absorption is found in the NIR of the spectrum. Further, a larger volume fraction of GZO attributes to the property of hyperbolic metamaterial. Moreover, the figure of merit and operational bandwidth are analyzed to optimize the absorption results. Such an absorber would be useful for energy harvesting, SWIR photodetectors, and imaging applications.