Polaritonic ENZ absorber for synthetic IR signature control

Identification of hazardous chemical, biological or explosive agents is safest when the observer is at standoff range. In the limiting case, airborne or space-based platforms may be used to detect the unique IR spectral fingerprint of a specific analyte; entirely removing the observer from the hazard vicinity. To cope with dynamic environmental conditions, however, these stand-off systems must be calibrated against known absorptions. Our team has developed a method of manufacturing thin-film IR absorbing materials using an epsilon-near-zero optical mode (ENZ). The absorption of the layer can be tuned within the 3-5 and 8-12 µm atmospheric transmission windows and layers can be ‘stacked’ to approximate the IR signatures of known analytes. Most importantly, the method of manufacture, PVD or sputtering, is highly scalable and can accommodate the large area substrates necessary for production of airborne and space-based stand-off detection calibration targets. In the proposed Phase I effort, Third Floor Materials will demonstrate the versatility of ENZ layers for synthetic IR signature control and present a credible manufacturing path to scale the absorber size to relevant dimensions for the US Army.