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Traditional cryogenic cooling methods, such as pulse-tube and reverse Brayton cryocoolers, are constrained by moving parts, high mass, and limited cooling capacity. Their mechanical complexity increases maintenance needs and reduces reliability, while their bulk adds significant weight penalties to mobile platforms. Although these systems can achieve kilowatt-scale cooling, they struggle to maintain stable, efficient performance under the continuous, high thermal loads required for megawatt-scale superconducting propulsion. The CryoQuad was developed specifically to address these shortcomings, delivering a lighter, more reliable, and higher-capacity solution tailored for superconducting electric propulsion systems. The novel design utilizes four thermoacoustic Stirling heat engines arranged a quarter wavelength apart in a quad loop configuration. This configuration – wherein each engine has high-power acoustic energy pulled off via power pulse-tube coolers – allows for rapid acoustic wave amplification without moving parts (e.g., pistons, turbines, pumps) or electricity. Importantly, the innovative design eliminates the need for large linear piston generators and large recuperator heat exchangers – two features common in megawatt-scale cryocooling pressure systems today – significantly reducing the overall system mass and complexity. While designed for use with liquid Helium, CryoQuad can utilize a variety of fluids depending on the required cryogenic temperatures. CryoQuad has the potential to be used in superconducting electric aircraft, other advanced propulsion systems, in-space cryogenic fluid management, cryosurgical cancer treatment probes, MRI systems, cryogenic cooling and packaging systems for superconducting electronics, space fuel depots, and other power applications. CryoQuad is available for patent licensing.

The ALD-Enhanced Far-to-Mid IR Camera Coating is fabricated by first applying a conductively loaded epoxy binder ~500 microns thick onto a conductive metal substrate (e.g., Cu, Al). This serves to provide high absorptance and low reflectance at the longest wavelength of interest, as well as to provide a mechanical buffer layer to reduce coating stress. Borosilicate glass microspheres are coated with a thin film metal via ALD, essentially turning the microspheres into resonators. That film is optically thin in the far infrared and approximates a resistive (~200 ohms per square) coating. Light trapped in the borosilicate glass microspheres is reflected back and forth within the glass–at each contact point, the light is attenuated by 50%. A monolayer of thin metal film-coated borosilicate glass microspheres is applied to the epoxy binder and cured, forming a robust mechanical structure that can be grounded to prevent deep dielectric charging by ionizing radiation in space. Once cured, the far-to-mid IR absorber structure can be coated with a traditional ~20-to-50 microns “black” absorptive paint to enhance the absorption band at short wavelengths, or a “white” diffusive paint to reject optical radiation. At this thickness and broad tolerance, the longwave response of the coating is preserved. Tailoring the electromagnetic properties of the coating layers and geometry enables realization of a broad band absorption response where the mass required per unit area has been minimized. While NASA originally developed the ALD-Enhanced Far-to-Mid IR Camera Coating for the Stratospheric Observatory for Infrared Astronomy mission, its robustness, absorptive qualities, and optical performance make it a significant addition to IR and terahertz imaging systems. The IR camera coating is at Technology Readiness Level (TRL) 3 (experimental proof-of-concept) and is available for patent licensing.

The Helmholtz Electric Machine addresses the fundamental challenge of integrating high-temperature superconductors into electric motor armatures through an innovative architectural approach. Unlike conventional motors where magnetic field orientation constantly shifts, this design uses two sets of magnetic field sources arranged as Helmholtz coils to generate a unidirectional magnetic field throughout operation. This configuration keeps the magnetic field aligned in-plane with the thin superconducting film, preventing the perpendicular orientation that causes excessive power losses. The reduction in armature power losses substantially eases the thermal management burden, making it practical to operate the armature at cryogenic temperatures required for HTS functionality. Predicted efficiency reaches 99.9%, representing a significant improvement over both conventional motors and non-HTS superconducting designs. An additional advantage of this motor architecture is its compatibility with liquid nitrogen cooling. The HTS materials operate at temperatures up to 77K, whereas competing superconductors require temperatures in the 20-35K range. Liquid nitrogen provides low-cost, high-performance cooling at 77K, but non-HTS superconducting motors must rely on liquid hydrogen (which poses safety concerns), costly helium gas, or experimental liquid neon. This operational temperature advantage reduces both complexity and operating costs for end users. The Helmholtz Electric Machine represents a breakthrough in superconducting motor design, combining unprecedented efficiency with practical cooling requirements to enable next-generation electric propulsion systems. The Helmholtz Electric Machine is available for patent licensing.