Advanced Spectrally Selective Materials for Obscurant Applications

Plasmonic metamaterials, composed of patterned metallic and dielectrics, can be engineered to have interesting optical properties that are attractive for a range of advanced obscurant applications. These particles are typically fabricated on planar surfaces, since patterning planar surfaces to achieve the desired effects is relatively straightforward.However, for planar geometries the particles optical properties are sensitive to the incoming radiations angle of incidence.This results in sub-optimal performance when a particles overall response is integrated over all possible incident angles.In fact, this angular dependence limits the maximum mass extinction coefficient obtainable using conventional infrared obscurant approaches, such as, shaped metal particles with high aspect ratios (e.g. rods, flakes). For an optimal obscurant particle, angle of incidence should ideally not play a critical role in the extinction performance