Infrared Spatial and Frequency Selective Metamaterial with Near-Unity Absorbance

We demonstrate, for the first time, a spatially dependent metamaterial perfect absorber operating in the infrared regime. We achieve an experimental absorption of 97% at a wavelength of $6.0\text{ }\ensuremath{\mu}\mathrm{m}$, and our results agree well with numerical full-wave simulations. By using two different metamaterial sublattices we experimentally demonstrate a spatial and frequency varying absorption which may have many relevant applications, including hyperspectral subsampling imaging.