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The broadband metamaterial termination for use in planar superconducting transmission lines has been successfully demonstrated in CLASS circuit structures as an effective termination. This metamaterial implementation is fully compatible with microfabrication techniques commonly used for microwave circuitry, and its response is insensitive to geometric tolerances, material properties, and interface details of conductive elements in device fabrication. In the context of far-infrared imaging, polarimetric, and superconducting integral field unit (IFU) spectrometer arrays for astrophysics, this strategy leads to higher performance, increased device yield, and greater overall circuit density. The metamaterial termination achieves a broadband absorption response with lower reflectance in a smaller physical footprint compared to existing adiabatic structures. This absorption response demonstrates significantly lower sensitivity to fabrication tolerances, material properties, and modeling assumptions than previous designs. These characteristics are critical for cryogenic applications, but the termination can also enhance the performance of room-temperature planar transmission line structures used in microwave engineering. The termination is realized as a lossy stepped impedance transition between Nb and PdAu, which reduces the total meander length, device footprint, and sensitivity to detailed implementation. This broadband metamaterial termination is applicable in superconducting technologies, including quantum communications, computing, and sensors. It has reached Technology Readiness Level (TRL) 7 (technology demonstrated in an operational environment) and is now available for patent licensing.

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.

NASA’s ESD is a small form-factor electromagnetic signal detector fabricated on a photonic crystal substrate (e.g., silicon-on-insulator wafer, III-V platform). It integrates a (1) miniature on-chip antenna (e.g., microstrip antenna) aligned to the desired operational frequency, (2) 2-D photonic crystal, and (3) electro-optic polymer (located on the photonic crystal). At the heart of the detector is the 2D photonic crystal. Using an array of carefully sized pores or “nano-cavities,” a waveguide is formed that governs the crystal’s optical transmission properties. An electro-optic polymer (a material that shifts its refractive index in response to external electric fields) is used to coat the photonic crystal. The combination of the 2D photonic crystal and EO polymer make up the resonator. A compact antenna with separate active feed and ground regions is placed near the photonic crystal, creating a gap through which the electromagnetic signal couples to the photonic crystal structure. Under normal conditions (no external signal), the EO polymer’s refractive index remains unchanged, producing a stable resonant notch in the device’s optical transmission. When the antenna intercepts an electromagnetic wave, the resulting electric field modifies the EO polymer’s refractive index, causing a measurable shift in the resonator’s optical output. By monitoring this shift, a photodetector can accurately determine the presence and magnitude of the incoming electromagnetic wave. NASA’s low SWaP-C, high precision ESD can be adapted for use in a variety of systems including remote sensing instruments (e.g., radiometers, spectrometers), transceivers for 5G communications networks, and other electromagnetic signal detection applications. The invention is available for patent licensing.

This CLAS-ACT is a lightweight, active phased array conformal antenna comprised of a thin multilayer microwave printed circuit board built on a flexible aerogel substrate using new methods of bonding. The aerogel substrate enables the antenna to be fitted onto curved surface. NASA's prototype operates at 11-15 GHz (Ku-band), but the design could be scaled to operate in the Ka-band (26 to 40 GHz). The antenna element design incorporates a dual stacked patch for wide bandwidth to operate on both the uplink and downlink frequencies with a common aperture. These elements are supported by a flexible variant of aerogel that allows the material to be thick in comparison to the wavelength of the signal with little to no additional weight. The conformal antenna offers advantages of better aerodynamics for the airframe, and potentially offers more physical area to either broadcast further distances or to broadcast at a higher data rate. The intended application for this antenna is for UAVs that need more than line of sight communications for command and control but cannot accommodate a large satellite dish. Examples may be UAVs intended for coastal monitoring, power line monitoring, emergency response, and border security where remote flying over large areas may be expected. Smaller UAVs may benefit greatly from the conformal antenna. Another possible application is a UAV mobile platform for Ku-band satellite communication. With the expectation that 5G will utilize microwave frequencies this technology may be of interest to other markets outside of satellite communications. For example, the automotive industry could benefit from a light weight conformal phased array for embedded radar. Also, the CLAS-ACT could be used for vehicle communications or even vehicle to vehicle communications.