Nanostructured
optical coatings with tailored spectral absorption properties are of interest
for a wide range of applications such as spectroscopy, emissivity control, and
solar energy harvesting. MRSEC
researchers have designed and demonstrated a broadband,
polarization-insensitive metamaterial with greater than 98% measured average
absorptivity that is maintained over a wide ±45°
field-of-view for mid-infrared wavelengths between 1.77 and 4.81 µm. This
work represents
a significant step toward realizing practical optical metamaterial absorbers
that provide near-perfect broadband absorption over a specified super-octave
bandwidth.