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The electromagnetic properties of the material are engineered by optimizing its complex dielectric function through the volume filling fraction of its components. A low-index polymeric binder, such as thermal polymers and epoxies, serves as the host medium to minimize reflectance in the conductively loaded dielectric media. To ensure thermal compatibility with metal substrates in cryogenic environments, dielectric powders are incorporated to match thermal expansion. Additionally, alumina frit compensates for thermal contraction at cryogenic temperatures, while non-magnetic conductive particles such as bronze, carbon allotropes, and degenerately doped silicon help tailor the material’s dielectric response. To enhance performance, small-particle scatterers reduce heat capacity and limit resonant dispersion, while dirty alloys stabilize resistance under conductive loading. The formulation incorporates reststrahlen materials and supports applications across the microwave to terahertz range, making it suitable for baffles, Lyot stops, and optical terminations, or as a primer for enhancing near-infrared and visible black paints. This high-emissivity, non-magnetic coating is designed for microwave to far-infrared instrumentation in space and cryogenic systems. It also benefits industries producing absorptive epoxies, EMI/EMC shielding, and quantum sensing components. It has reached Technology Readiness Level (TRL) 5 (component validation in relevant environment) and is now available for patent licensing.

This NASA technology transforms a conventional infrared (IR) imaging system into a multi-wavelength imaging pyrometer using a tunable optical filter. The actively tunable optical filter is based on an exotic phase-change material (PCM) which exhibits a large reversible refractive index shift through an applied energetic stimulus. This change is non-volatile, and no additional energy is required to maintain its state once set. The filter is placed between the scene and the imaging sensor and switched between user selected center-wavelengths to create a series of single-wavelength, monochromatic, two-dimensional images. At the pixel level, the intensity values of these monochromatic images represent the wavelength-dependent, blackbody energy emitted by the object due to its temperature. Ratioing the measured spectral irradiance for each wavelength yields emissivity-independent temperature data at each pixel. The filter’s Center Wavelength (CWL) and Full Width Half Maximum (FWHM), which are related to the quality factor (Q) of the filter, are actively tunable on the order of nanoseconds-microseconds (GHz-MHz). This behavior is electronically controlled and can be operated time-sequentially (on a nanosecond time scale) in the control electronics, a capability not possible with conventional optical filtering technologies.